Timelapse of a three-dimensional printer in action

3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model.[1][2][3] It can be done in a variety of processes in which material is deposited, joined or solidified under computer control,[4] with the material being added together (such as plastics, liquids or powder grains being fused), typically layer by layer.

In the 1980s, 3D printing techniques were considered suitable only for the production of functional or aesthetic prototypes, and a more appropriate term for it at the time was rapid prototyping.[5] As of 2019, the precision, repeatability, and material range of 3D printing have increased to the point that some 3D printing processes are considered viable as an industrial-production technology; in this context, the term additive manufacturing can be used synonymously with 3D printing.[6] One of the key advantages of 3D printing[7] is the ability to produce very complex shapes or geometries that would be otherwise infeasible to construct by hand, including hollow parts or parts with internal truss structures to reduce weight while creating less material waste. Fused deposition modeling (FDM), which uses a continuous filament of a thermoplastic material, is the most common 3D printing process in use as of 2020.[8]


The umbrella term additive manufacturing (AM) gained popularity in the 2000s,[9] inspired by the theme of material being added together (in any of various ways). In contrast, the term subtractive manufacturing appeared as a retronym for the large family of machining processes with material removal as their common process. The term 3D printing still referred only to the polymer technologies in most minds, and the term AM was more likely to be used in metalworking and end-use part production contexts than among polymer, inkjet, or stereolithography enthusiasts.

By the early 2010s, the terms 3D printing and additive manufacturing evolved senses in which they were alternate umbrella terms for additive technologies, one being used in popular language by consumer-maker communities and the media, and the other used more formally by industrial end-use part producers, machine manufacturers, and global technical standards organizations. Until recently, the term 3D printing has been associated with machines low in price or capability.[10] 3D printing and additive manufacturing reflect that the technologies share the theme of material addition or joining throughout a 3D work envelope under automated control. Peter Zelinski, the editor-in-chief of Additive Manufacturing magazine, pointed out in 2017 that the terms are still often synonymous in casual usage,[11] but some manufacturing industry experts are trying to make a distinction whereby additive manufacturing comprises 3D printing plus other technologies or other aspects of a manufacturing process.[11]

Other terms that have been used as synonyms or hypernyms have included desktop manufacturing, rapid manufacturing (as the logical production-level successor to rapid prototyping), and on-demand manufacturing (which echoes on-demand printing in the 2D sense of printing). The fact that the application of the adjectives rapid and on-demand to the noun manufacturing was novel in the 2000s reveals the long-prevailing mental model of the previous industrial era during which almost all production manufacturing had involved long lead times for laborious tooling development. Today, the term subtractive has not replaced the term machining, instead complementing it when a term that covers any removal method is needed. Agile tooling is the use of modular means to design tooling that is produced by additive manufacturing or 3D printing methods to enable quick prototyping and responses to tooling and fixture needs. Agile tooling uses a cost-effective and high-quality method to quickly respond to customer and market needs, and it can be used in hydro-forming, stamping, injection molding and other manufacturing processes.


1940s and 1950s

The general concept of and procedure to be used in 3D-printing was first described by Murray Leinster in his 1945 short story "Things Pass By": "But this constructor is both efficient and flexible. I feed magnetronic plastics — the stuff they make houses and ships of nowadays — into this moving arm. It makes drawings in the air following drawings it scans with photo-cells. But plastic comes out of the end of the drawing arm and hardens as it comes ... following drawings only"[12]

It was also described by Raymond F. Jones in his story, "Tools of the Trade", published in the November 1950 issue of Astounding Science Fiction magazine. He referred to it as a "molecular spray" in that story.


In 1971, Johannes F Gottwald patented the Liquid Metal Recorder, U.S. patent 3596285A,[13] a continuous inkjet metal material device to form a removable metal fabrication on a reusable surface for immediate use or salvaged for printing again by remelting. This appears to be the first patent describing 3D printing with rapid prototyping and controlled on-demand manufacturing of patterns.

The patent states:

As used herein the term printing is not intended in a limited sense but includes writing or other symbols, character or pattern formation with an ink. The term ink as used in is intended to include not only dye or pigment-containing materials, but any flowable substance or composition suited for application to the surface for forming symbols, characters, or patterns of intelligence by marking. The preferred ink is of a hot melt type. The range of commercially available ink compositions which could meet the requirements of the invention are not known at the present time. However, satisfactory printing according to the invention has been achieved with the conductive metal alloy as ink.

But in terms of material requirements for such large and continuous displays, if consumed at theretofore known rates, but increased in proportion to increase in size, the high cost would severely limit any widespread enjoyment of a process or apparatus satisfying the foregoing objects.

It is therefore an additional object of the invention to minimize use to materials in a process of the indicated class.

It is a further object of the invention that materials employed in such a process be salvaged for reuse.

According to another aspect of the invention, a combination for writing and the like comprises a carrier for displaying an intelligence pattern and an arrangement for removing the pattern from the carrier.

In 1974, David E. H. Jones laid out the concept of 3D printing in his regular column Ariadne in the journal New Scientist.[14][15]


Early additive manufacturing equipment and materials were developed in the 1980s.[16]

In April 1980, Hideo Kodama of Nagoya Municipal Industrial Research Institute invented two additive methods for fabricating three-dimensional plastic models with photo-hardening thermoset polymer, where the UV exposure area is controlled by a mask pattern or a scanning fiber transmitter.[17] He filed a patent for this XYZ plotter, which was published on 10 November 1981. (JP S56-144478).[18] His research results as journal papers were published in April and November of 1981.[19][20] However, there was no reaction to the series of his publications. His device was not highly evaluated in the laboratory and his boss did not show any interest. His research budget was just 60,000 yen or $545 a year. Acquiring the patent rights for the XYZ plotter was abandoned, and the project was terminated.

A US 4323756 patent, method of fabricating articles by sequential deposition, granted on 6 April 1982 to Raytheon Technologies Corp describes using hundreds or thousands of "layers" of powdered metal and a laser energy source and represents an early reference to forming "layers" and the fabrication of articles on a substrate.

On 2 July 1984, American entrepreneur Bill Masters filed a patent for his computer automated manufacturing process and system (US 4665492).[21] This filing is on record at the USPTO as the first 3D printing patent in history; it was the first of three patents belonging to Masters that laid the foundation for the 3D printing systems used today.[22][23]

On 16 July 1984, Alain Le Méhauté, Olivier de Witte, and Jean Claude André filed their patent for the stereolithography process.[24] The application of the French inventors was abandoned by the French General Electric Company (now Alcatel-Alsthom) and CILAS (The Laser Consortium).[25] The claimed reason was "for lack of business perspective".[26]

In 1983, Robert Howard started R.H. Research, later named Howtek, Inc. in Feb 1984 to develop a color inkjet 2D printer, Pixelmaster, commercialized in 1986, using Thermoplastic (hot-melt) plastic ink.[27] A team was put together, 6 members[27] from Exxon Office Systems, Danbury Systems Division, an inkjet printer startup and some members of Howtek, Inc group who became popular figures in the 3D printing industry. One Howtek member, Richard Helinski (patent US5136515A, Method and Means for constructing three-dimensional articles by particle deposition, application 11/07/1989 granted 8/04/1992) formed a New Hampshire company C.A.D-Cast, Inc, name later changed to Visual Impact Corporation (VIC) on 8/22/1991. A prototype of the VIC 3D printer for this company is available with a video presentation showing a 3D model printed with a single nozzle inkjet. Another employee Herbert Menhennett formed a New Hampshire company HM Research in 1991 and introduced the Howtek, Inc, inkjet technology and thermoplastic materials to Royden Sanders of SDI and Bill Masters of Ballistic Particle Manufacturing (BPM) where he worked for a number of years. Both BPM 3D printers and SPI 3D printers use Howtek, Inc style Inkjets and Howtek, Inc style materials. Royden Sanders licensed the Helinksi patent prior to manufacturing the Modelmaker 6 Pro at Sanders prototype, Inc (SPI) in 1993. James K. McMahon who was hired by Howtek, Inc to help develop the inkjet, later worked at Sanders Prototype and now operates Layer Grown Model Technology, a 3D service provider specializing in Howtek single nozzle inkjet and SDI printer support. James K. McMahon worked with Steven Zoltan, 1972 drop-on-demand inkjet inventor, at Exxon and has a patent in 1978 that expanded the understanding of the single nozzle design inkjets (Alpha jets) and helped perfect the Howtek, Inc hot-melt inkjets. This Howtek hot-melt thermoplastic technology is popular with metal investment casting, especially in the 3D printing jewelry industry.[28] Sanders (SDI) first Modelmaker 6Pro customer was Hitchner Corporations, Metal Casting Technology, Inc in Milford, NH a mile from the SDI facility in late 1993-1995 casting golf clubs and auto engine parts.

On 8 August 1984 a patent, US4575330, assigned to UVP, Inc., later assigned to Chuck Hull of 3D Systems Corporation[29] was filed, his own patent for a stereolithography fabrication system, in which individual laminae or layers are added by curing photopolymers with impinging radiation, particle bombardment, chemical reaction or just ultraviolet light lasers. Hull defined the process as a "system for generating three-dimensional objects by creating a cross-sectional pattern of the object to be formed".[30][31] Hull's contribution was the STL (Stereolithography) file format and the digital slicing and infill strategies common to many processes today. In 1986, Charles "Chuck" Hull was granted a patent for this system, and his company, 3D Systems Corporation was formed and it released the first commercial 3D printer, the SLA-1,[32] later in 1987 or 1988.

The technology used by most 3D printers to date—especially hobbyist and consumer-oriented models—is fused deposition modeling, a special application of plastic extrusion, developed in 1988 by S. Scott Crump and commercialized by his company Stratasys, which marketed its first FDM machine in 1992.[28]

Owning a 3D printer in the 1980s cost upwards of $300,000 ($650,000 in 2016 dollars).[33]


AM processes for metal sintering or melting (such as selective laser sintering, direct metal laser sintering, and selective laser melting) usually went by their own individual names in the 1980s and 1990s. At the time, all metalworking was done by processes that are now called non-additive (casting, fabrication, stamping, and machining); although plenty of automation was applied to those technologies (such as by robot welding and CNC), the idea of a tool or head moving through a 3D work envelope transforming a mass of raw material into a desired shape with a toolpath was associated in metalworking only with processes that removed metal (rather than adding it), such as CNC milling, CNC EDM, and many others. However, the automated techniques that added metal, which would later be called additive manufacturing, were beginning to challenge that assumption. By the mid-1990s, new techniques for material deposition were developed at Stanford and Carnegie Mellon University, including microcasting[34] and sprayed materials.[35] Sacrificial and support materials had also become more common, enabling new object geometries.[36]

The term 3D printing originally referred to a powder bed process employing standard and custom inkjet print heads, developed at MIT by Emanuel Sachs in 1993 and commercialized by Soligen Technologies, Extrude Hone Corporation, and Z Corporation.[citation needed]

The year 1993 also saw the start of an inkjet 3D printer company initially named Sanders Prototype, Inc and later named Solidscape, introducing a high-precision polymer jet fabrication system with soluble support structures, (categorized as a "dot-on-dot" technique).[28]

In 1995 the Fraunhofer Society developed the selective laser melting process.


In the early 2000s 3D printers were still largely being used just in the manufacturing and research industries, as the technology was still relatively young and was too expensive for most consumers to be able to get their hands on. The 2000s was when larger scale use of the technology began being seen in industry, most often in the architecture and medical industries, though it was typically used for low accuracy modeling and testing, rather than the production of common manufactured goods or heavy prototyping.[37]

In 2005 users began to design and distribute plans for 3D printers that could print around 70% of their own parts, the original plans of which were designed by Adrian Bowyer at the University of Bath in 2004, with the name of the project being RepRap (Replicating Rapid-prototyper).[38]

Similarly, in 2006 the Fab@Home project was started by Evan Malone and Hod Lipson, another project whose purpose was to design a low-cost and open source fabrication system that users could develop on their own and post feedback on, making the project very collaborative.[39]

Much of the software for 3D printing available to the public at the time was open source, and as such was quickly distributed and improved upon by many individual users. In 2009 the Fused Deposition Modeling (FDM) printing process patents expired. This opened the door to a new wave of startup companies, many of which were established by major contributors of these open source initiatives, with the goal of many of them being to start developing commercial FDM 3D printers that were more accessible to the general public.[40]


As the various additive processes matured, it became clear that soon metal removal would no longer be the only metalworking process done through a tool or head moving through a 3D work envelope, transforming a mass of raw material into a desired shape layer by layer. The 2010s were the first decade in which metal end-use parts such as engine brackets[41] and large nuts[42] would be grown (either before or instead of machining) in job production rather than obligately being machined from bar stock or plate. It is still the case that casting, fabrication, stamping, and machining are more prevalent than additive manufacturing in metalworking, but AM is now beginning to make significant inroads, and with the advantages of design for additive manufacturing, it is clear to engineers that much more is to come.

One place that AM is making a significant inroad is in the aviation industry. With nearly 3.8 billion air travelers in 2016,[43] the demand for fuel efficient and easily produced jet engines has never been higher. For large OEMs (original equipment manufacturers) like Pratt and Whitney (PW) and General Electric (GE) this means looking towards AM as a way to reduce cost, reduce the number of nonconforming parts, reduce weight in the engines to increase fuel efficiency and find new, highly complex shapes that would not be feasible with the antiquated manufacturing methods. One example of AM integration with aerospace was in 2016 when Airbus delivered the first of GE's LEAP engines. This engine has integrated 3D printed fuel nozzles, reducing parts from 20 to 1, a 25% weight reduction, and reduced assembly times.[44] A fuel nozzle is the perfect inroad for additive manufacturing in a jet engine since it allows for optimized design of the complex internals and it is a low-stress, non-rotating part. Similarly, in 2015, PW delivered their first AM parts in the PurePower PW1500G to Bombardier. Sticking to low-stress, non-rotating parts, PW selected the compressor stators and synch ring brackets[45] to roll out this new manufacturing technology for the first time. While AM is still playing a small role in the total number of parts in the jet engine manufacturing process, the return on investment can already be seen by the reduction in parts, the rapid production capabilities and the "optimized design in terms of performance and cost".[46]

As technology matured, several authors began to speculate that 3D printing could aid in sustainable development in the developing world.[47]

In 2012, Filabot developed a system for closing the loop[48] with plastic and allows for any FDM or FFF 3D printer to be able to print with a wider range of plastics.

In 2014, Benjamin S. Cook and Manos M. Tentzeris demonstrated the first multi-material, vertically integrated printed electronics additive manufacturing platform (VIPRE) which enabled 3D printing of functional electronics operating up to 40 GHz.[49]

As the price of printers started to drop people interested in this technology had more access and freedom to make what they wanted. As of 2014, the price for commercial printers was still high with the cost being over $2,000.[50]

The term "3D printing" originally referred to a process that deposits a binder material onto a powder bed with inkjet printer heads layer by layer. More recently, the popular vernacular has started using the term to encompass a wider variety of additive-manufacturing techniques such as electron-beam additive manufacturing and selective laser melting. The United States and global technical standards use the official term additive manufacturing for this broader sense.

The most commonly used 3D printing process (46% as of 2018) is a material extrusion technique called fused deposition modeling, or FDM.[8] While FDM technology was invented after the other two most popular technologies, stereolithography (SLA) and selective laser sintering (SLS), FDM is typically the most inexpensive of the three by a large margin,[citation needed] which lends to the popularity of the process.


As of 2020, 3D printers have reached the level of quality and price that allows most people to enter the world of 3D printing. In 2020 decent quality printers can be found for less than US$200 for entry-level machines. These more affordable printers are usually fused deposition modeling (FDM) printers.[51]

In November 2021 a British patient named Steve Verze received the world's first fully 3D-printed prosthetic eye from the Moorfields Eye Hospital in London.[52][53]

In April 2024, the world's largest 3D printer, the Factory of the Future 1.0 was revealed at the University of Maine. It is able to make objects 96 feet long, or 29 meters.[54]

In 2024, researchers used machine learning to improve the construction of synthetic bone[55] and set a record for shock absorption.[56]

Benefits of 3D printing

Additive manufacturing or 3D printing has rapidly gained importance in the field of engineering due to its many benefits. The vision of 3D printing is design freedom, individualization,[57] decentralization[58] and executing processes that were previously impossible through alternative methods.[59] Some of these benefits include enabling faster prototyping, reducing manufacturing costs, increasing product customization, and improving product quality.[60]

Furthermore, the capabilities of 3D printing have extended beyond traditional manufacturing, like lightweight construction,[61] or repair and maintenance[62] with applications in prosthetics,[63] bioprinting,[64] food industry,[65] rocket building,[66] design and art[67] and renewable energy systems.[68] 3D printing technology can be used to produce battery energy storage systems, which are essential for sustainable energy generation and distribution.

Another benefit of 3D printing is the technology's ability to produce complex geometries with high precision and accuracy.[69] This is particularly relevant in the field of microwave engineering, where 3D printing can be used to produce components with unique properties that are difficult to achieve using traditional manufacturing methods.[70]

General principles


Main article: 3D modeling

CAD model used for 3D printing
3D models can be generated from 2D pictures taken at a 3D photo booth.

3D printable models may be created with a computer-aided design (CAD) package, via a 3D scanner, or by a plain digital camera and photogrammetry software. 3D printed models created with CAD result in relatively fewer errors than other methods. Errors in 3D printable models can be identified and corrected before printing.[71] The manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting. 3D scanning is a process of collecting digital data on the shape and appearance of a real object, and creating a digital model based on it.

CAD models can be saved in the stereolithography file format (STL), a de facto CAD file format for additive manufacturing that stores data based on triangulations of the surface of CAD models. STL is not tailored for additive manufacturing because it generates large file sizes of topology-optimized parts and lattice structures due to the large number of surfaces involved. A newer CAD file format, the additive manufacturing file format (AMF), was introduced in 2011 to solve this problem. It stores information using curved triangulations.[72]


Before printing a 3D model from an STL file, it must first be examined for errors. Most CAD applications produce errors in output STL files,[73][74] of the following types:

A step in the STL generation known as "repair" fixes such problems in the original model.[77][78] Generally, STLs that have been produced from a model obtained through 3D scanning often have more of these errors[79] as 3D scanning is often achieved by point to point acquisition/mapping. 3D reconstruction often includes errors.[80]

Once completed, the STL file needs to be processed by a piece of software called a "slicer", which converts the model into a series of thin layers and produces a G-code file containing instructions tailored to a specific type of 3D printer (FDM printers).[81] This G-code file can then be printed with 3D printing client software (which loads the G-code and uses it to instruct the 3D printer during the 3D printing process).

Printer resolution describes layer thickness and X–Y resolution in dots per inch (dpi) or micrometers (μm). Typical layer thickness is around 100 μm (250 DPI), although some machines can print layers as thin as 16 μm (1,600 DPI).[82] X–Y resolution is comparable to that of laser printers. The particles (3D dots) are around 0.01 to 0.1 μm (2,540,000 to 250,000 DPI) in diameter.[83] For that printer resolution, specifying a mesh resolution of 0.01–0.03 mm and a chord length ≤ 0.016 mm generates an optimal STL output file for a given model input file.[84] Specifying higher resolution results in larger files without increase in print quality.

3:30 Timelapse of an 80-minute video of an object being made out of PLA using molten polymer deposition

Construction of a model with contemporary methods can take anywhere from several hours to several days, depending on the method used and the size and complexity of the model. Additive systems can typically reduce this time to a few hours, although it varies widely depending on the type of machine used and the size and number of models being produced simultaneously.


Though the printer-produced resolution and surface finish are sufficient for some applications, post-processing and finishing methods allow for benefits such as greater dimensional accuracy, smoother surfaces, and other modifications such as coloration.

The surface finish of a 3D printed part can improved using subtractive methods such as sanding and bead blasting. When smoothing parts that require dimensional accuracy, it is important to take into account the volume of the material being removed.[85]

Some printable polymers, such as acrylonitrile butadiene styrene (ABS), allow the surface finish to be smoothed and improved using chemical vapor processes[86] based on acetone or similar solvents.

Some additive manufacturing techniques can benefit from annealing as a post-processing step. Annealing a 3D-printed part allows for better internal layer bonding due to recrystallization of the part. It allows for an increase in mechanical properties, some of which are fracture toughness,[87] flexural strength,[88] impact resistance,[89] and heat resistance.[89] Annealing a component may not be suitable for applications where dimensional accuracy is required, as it can introduce warpage or shrinkage due to heating and cooling.[90]

Additive or subtractive hybrid manufacturing (ASHM) is a method that involves producing a 3D printed part and using machining (subtractive manufacturing) to remove material.[91] Machining operations can be completed after each layer, or after the entire 3D print has been completed depending on the application requirements. These hybrid methods allow for 3D-printed parts to achieve better surface finishes and dimensional accuracy.[92]

The layered structure of traditional additive manufacturing processes leads to a stair-stepping effect on part-surfaces that are curved or tilted with respect to the building platform. The effect strongly depends on the layer height used, as well as the orientation of a part surface inside the building process.[93] This effect can be minimized using "variable layer heights" or "adaptive layer heights". These methods decrease the layer height in places where higher quality is needed.[94]

Painting a 3D-printed part offers a range of finishes and appearances that may not be achievable through most 3D printing techniques. The process typically involves several steps, such as surface preparation, priming, and painting.[95] These steps help prepare the surface of the part and ensuring the paint adheres properly.

Some additive manufacturing techniques are capable of using multiple materials simultaneously. These techniques are able to print in multiple colors and color combinations simultaneously and can produce parts that may not necessarily require painting.

Some printing techniques require internal supports to be built to support overhanging features during construction. These supports must be mechanically removed or dissolved if using a water-soluble support material such as PVA after completing a print.

Some commercial metal 3D printers involve cutting the metal component off the metal substrate after deposition. A new process for the GMAW 3D printing allows for substrate surface modifications to remove aluminium[96] or steel.[97]


Detail of the Stoofbrug [nl] in Amsterdam, the world's first 3D-printed metal bridge[98]

Traditionally, 3D printing focused on polymers for printing, due to the ease of manufacturing and handling polymeric materials. However, the method has rapidly evolved to not only print various polymers[99] but also metals[100][101] and ceramics,[102] making 3D printing a versatile option for manufacturing. Layer-by-layer fabrication of three-dimensional physical models is a modern concept that "stems from the ever-growing CAD industry, more specifically the solid modeling side of CAD. Before solid modeling was introduced in the late 1980s, three-dimensional models were created with wire frames and surfaces."[103] but in all cases the layers of materials are controlled by the printer and the material properties. The three-dimensional material layer is controlled by the deposition rate as set by the printer operator and stored in a computer file. The earliest printed patented material was a hot melt type ink for printing patterns using a heated metal alloy.

Charles Hull filed the first patent on August 8, 1984, to use a UV-cured acrylic resin using a UV-masked light source at UVP Corp to build a simple model. The SLA-1 was the first SL product announced by 3D Systems at Autofact Exposition, Detroit, November 1978. The SLA-1 Beta shipped in Jan 1988 to Baxter Healthcare, Pratt and Whitney, General Motors and AMP. The first production SLA-1 shipped to Precision Castparts in April 1988. The UV resin material changed over quickly to an epoxy-based material resin. In both cases, SLA-1 models needed UV oven curing after being rinsed in a solvent cleaner to remove uncured boundary resin. A post cure apparatus (PCA) was sold with all systems. The early resin printers required a blade to move fresh resin over the model on each layer. The layer thickness was 0.006 inches and the HeCd laser model of the SLA-1 was 12 watts and swept across the surface at 30 in per second. UVP was acquired by 3D Systems in January 1990.[104]

A review of the history shows that a number of materials (resins, plastic powder, plastic filament and hot-melt plastic ink) were used in the 1980s for patents in the rapid prototyping field. Masked lamp UV-cured resin was also introduced by Cubital's Itzchak Pomerantz in the Soldier 5600, Carl Deckard's (DTM) laser sintered thermoplastic powders, and adhesive-laser cut paper (LOM) stacked to form objects by Michael Feygin before 3D Systems made its first announcement. Scott Crump was also working with extruded "melted" plastic filament modeling (FDM) and drop deposition had been patented by William E Masters a week after Hull's patent in 1984, but he had to discover thermoplastic inkjets, introduced by Visual Impact Corporation 3D printer in 1992, using inkjets from Howtek, Inc., before he formed BPM to bring out his own 3D printer product in 1994.[104]

Multi-material 3D printing

Main article: Multi-material 3D printing

A multi-material 3DBenchy

Efforts to achieve multi-material 3D printing range from enhanced FDM-like processes like VoxelJet to novel voxel-based printing technologies like layered assembly.[105]

A drawback of many existing 3D printing technologies is that they only allow one material to be printed at a time, limiting many potential applications that require the integration of different materials in the same object. Multi-material 3D printing solves this problem by allowing objects of complex and heterogeneous arrangements of materials to be manufactured using a single printer. Here, a material must be specified for each voxel (or 3D printing pixel element) inside the final object volume.

The process can be fraught with complications, however, due to the isolated and monolithic algorithms. Some commercial devices have sought to solve these issues, such as building a Spec2Fab translator, but the progress is still very limited.[106] Nonetheless, in the medical industry, a concept of 3D printed pills and vaccines has been presented.[107] With this new concept, multiple medications can be combined, which is expected to decrease many risks. With more and more applications of multi-material 3D printing, the costs of daily life and high technology development will become inevitably lower.

Metallographic materials of 3D printing is also being researched.[108] By classifying each material, CIMP-3D can systematically perform 3D printing with multiple materials.[109]

4D printing

Main article: 4D printing

Using 3D printing and multi-material structures in additive manufacturing has allowed for the design and creation of what is called 4D printing. 4D printing is an additive manufacturing process in which the printed object changes shape with time, temperature, or some other type of stimulation. 4D printing allows for the creation of dynamic structures with adjustable shapes, properties or functionality. The smart/stimulus-responsive materials that are created using 4D printing can be activated to create calculated responses such as self-assembly, self-repair, multi-functionality, reconfiguration and shape-shifting. This allows for customized printing of shape-changing and shape-memory materials.[110]

4D printing has the potential to find new applications and uses for materials (plastics, composites, metals, etc.) and has the potential to create new alloys and composites that were not viable before. The versatility of this technology and materials can lead to advances in multiple fields of industry, including space, commercial and medical fields. The repeatability, precision, and material range for 4D printing must increase to allow the process to become more practical throughout these industries. 

To become a viable industrial production option, there are a few challenges that 4D printing must overcome. The challenges of 4D printing include the fact that the microstructures of these printed smart materials must be close to or better than the parts obtained through traditional machining processes. New and customizable materials need to be developed that have the ability to consistently respond to varying external stimuli and change to their desired shape. There is also a need to design new software for the various technique types of 4D printing. The 4D printing software will need to take into consideration the base smart material, printing technique, and structural and geometric requirements of the design.[111]

Processes and printers

Main article: 3D printing processes

This section should include only a brief summary of 3D printing processes. See Wikipedia:Summary style for information on how to properly incorporate it into this article's main text. (August 2017)

ISO/ASTM52900-15 defines seven categories of additive manufacturing (AM) processes within its meaning.[112][113] They are:

The main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object.[114] Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities.[115] Printers that work directly with metals are generally expensive. However, less expensive printers can be used to make a mold, which is then used to make metal parts.[116]

Material jetting

The first process where three-dimensional material is deposited to form an object was done with material jetting[28] or as it was originally called particle deposition. Particle deposition by inkjet first started with continuous inkjet technology (CIT) (1950s) and later with drop-on-demand inkjet technology (1970s) using hot-melt inks. Wax inks were the first three-dimensional materials jetted and later low-temperature alloy metal was jetted with CIT. Wax and thermoplastic hot melts were jetted next by DOD. Objects were very small and started with text characters and numerals for signage. An object must have form and can be handled. Wax characters tumbled off paper documents and inspired a liquid metal recorder patent to make metal characters for signage in 1971. Thermoplastic color inks (CMYK) were printed with layers of each color to form the first digitally formed layered objects in 1984. The idea of investment casting with Solid-Ink jetted images or patterns in 1984 led to the first patent to form articles from particle deposition in 1989, issued in 1992.

Material extrusion

Schematic representation of the 3D printing technique known as fused filament fabrication; a filament "a)" of plastic material is fed through a heated moving head "b)" that melts and extrudes it depositing it, layer after layer, in the desired shape "c). A moving platform "e)" lowers after each layer is deposited. For this kind of technology, additional vertical support structures "d)" are needed to sustain overhanging parts

Some methods melt or soften the material to produce the layers. In fused filament fabrication, also known as fused deposition modeling (FDM), the model or part is produced by extruding small beads or streams of material that harden immediately to form layers. A filament of thermoplastic, metal wire, or other material is fed into an extrusion nozzle head (3D printer extruder), which heats the material and turns the flow on and off. FDM is somewhat restricted in the variation of shapes that may be fabricated. Another technique fuses parts of the layer and then moves upward in the working area, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece.[117] Recently, FFF/FDM has expanded to 3-D print directly from pellets to avoid the conversion to filament. This process is called fused particle fabrication (FPF) (or fused granular fabrication (FGF) and has the potential to use more recycled materials.[118]

Powder bed fusion

Powder bed fusion techniques, or PBF, include several processes such as DMLS, SLS, SLM, MJF and EBM. Powder bed fusion processes can be used with an array of materials and their flexibility allows for geometrically complex structures,[119] making it a good choice for many 3D printing projects. These techniques include selective laser sintering, with both metals and polymers and direct metal laser sintering.[120] Selective laser melting does not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layer-wise method that has mechanical properties similar to those of conventional manufactured metals. Electron beam melting is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum.[121][122] Another method consists of an inkjet 3D printing system, which creates the model one layer at a time by spreading a layer of powder (plaster or resins) and printing a binder in the cross-section of the part using an inkjet-like process. With laminated object manufacturing, thin layers are cut to shape and joined. In addition to the previously mentioned methods, HP has developed the Multi Jet Fusion (MJF) which is a powder base technique, though no lasers are involved. An inkjet array applies fusing and detailing agents which are then combined by heating to create a solid layer.[123]

Binder jetting

The binder jetting 3D printing technique involves the deposition of a binding adhesive agent onto layers of material, usually powdered, and then this "green" state part may be cured and even sintered. The materials can be ceramic-based, metal or plastic. This method is also known as inkjet 3D printing. To produce a part, the printer builds the model using a head that moves over the platform base to spread or deposit alternating layers of powder (plaster and resins) and binder. Most modern binder jet printers also cure each layer of binder. These steps are repeated until all layers have been printed. This green part is usually cured in an oven to off-gas most of the binder before being sintered in a kiln with a specific time-temperature curve for the given material(s).

This technology allows the printing of full-color prototypes, overhangs, and elastomer parts. The strength of bonded powder prints can be enhanced by impregnating in the spaces between the necked or sintered matrix of powder with other compatible materials depending on the powder material, like wax, thermoset polymer, or even bronze.[124][125]

Schematic representation of stereolithography; a light-emitting device a) (laser or DLP) selectively illuminate the transparent bottom c) of a tank b) filled with a liquid photo-polymerizing resin; the solidified resin d) is progressively dragged up by a lifting platform e)


Other methods cure liquid materials using different sophisticated technologies, such as stereolithography. Photopolymerization is primarily used in stereolithography to produce a solid part from a liquid. Inkjet printer systems like the Objet PolyJet system spray photopolymer materials onto a build tray in ultra-thin layers (between 16 and 30 μm) until the part is completed.[126] Each photopolymer layer is cured with UV light after it is jetted, producing fully cured models that can be handled and used immediately, without post-curing. Ultra-small features can be made with the 3D micro-fabrication technique used in multiphoton photopolymerisation. Due to the nonlinear nature of photo excitation, the gel is cured to a solid only in the places where the laser was focused while the remaining gel is then washed away. Feature sizes of under 100 nm are easily produced, as well as complex structures with moving and interlocked parts.[127] Yet another approach uses a synthetic resin that is solidified using LEDs.[128]

In Mask-image-projection-based stereolithography, a 3D digital model is sliced by a set of horizontal planes. Each slice is converted into a two-dimensional mask image. The mask image is then projected onto a photocurable liquid resin surface and light is projected onto the resin to cure it in the shape of the layer.[129] Continuous liquid interface production begins with a pool of liquid photopolymer resin. Part of the pool bottom is transparent to ultraviolet light (the "window"), which causes the resin to solidify. The object rises slowly enough to allow the resin to flow under and maintain contact with the bottom of the object.[130] In powder-fed directed-energy deposition, a high-power laser is used to melt metal powder supplied to the focus of the laser beam. The powder-fed directed energy process is similar to selective laser sintering, but the metal powder is applied only where material is being added to the part at that moment.[131][132]

Computed axial lithography

Computed axial lithography is a method for 3D printing based on computerised tomography scans to create prints in photo-curable resin. It was developed by a collaboration between the University of California, Berkeley with Lawrence Livermore National Laboratory.[133][134][135] Unlike other methods of 3D printing it does not build models through depositing layers of material like fused deposition modelling and stereolithography, instead it creates objects using a series of 2D images projected onto a cylinder of resin.[133][135] It is notable for its ability to build an object much more quickly than other methods using resins and the ability to embed objects within the prints.[134]

Liquid additive manufacturing

Liquid additive manufacturing (LAM) is a 3D printing technique that deposits a liquid or high viscose material (e.g. liquid silicone rubber) onto a build surface to create an object which then is vulcanised using heat to harden the object.[136][137][138] The process was originally created by Adrian Bowyer and was then built upon by German RepRap.[136][139][140]

A technique called programmable tooling uses 3D printing to create a temporary mold, which is then filled via a conventional injection molding process and then immediately dissolved.[141]


In some printers, paper can be used as the build material, resulting in a lower cost to print. During the 1990s some companies marketed printers that cut cross-sections out of special adhesive coated paper using a carbon dioxide laser and then laminated them together.

In 2005 Mcor Technologies Ltd developed a different process using ordinary sheets of office paper, a tungsten carbide blade to cut the shape, and selective deposition of adhesive and pressure to bond the prototype.[142]

Directed-energy deposition (DED)

Powder-fed directed-energy deposition

In powder-fed directed-energy deposition (also known as laser metal deposition), a high-power laser is used to melt metal powder supplied to the focus of the laser beam. The laser beam typically travels through the center of the deposition head and is focused on a small spot by one or more lenses. The build occurs on an X-Y table which is driven by a tool path created from a digital model to fabricate an object layer by layer. The deposition head is moved up vertically as each layer is completed. Some systems even make use of 5-axis[143][144] or 6-axis systems[145] (i.e. articulated arms) capable of delivering material on the substrate (a printing bed, or a pre-existing part[146]) with few to no spatial access restrictions. Metal powder is delivered and distributed around the circumference of the head or can be split by an internal manifold and delivered through nozzles arranged in various configurations around the deposition head. A hermetically sealed chamber filled with inert gas or a local inert shroud gas (sometimes both combined) is often used to shield the melt pool from atmospheric oxygen, to limit oxidation and to better control the material properties. The powder-fed directed-energy process is similar to selective laser sintering, but the metal powder is projected only where the material is being added to the part at that moment. The laser beam is used to heat up and create a "melt pool" on the substrate, in which the new powder is injected quasi-simultaneously. The process supports a wide range of materials including titanium, stainless steel, aluminium, tungsten, and other specialty materials as well as composites and functionally graded materials. The process can not only fully build new metal parts but can also add material to existing parts for example for coatings, repair, and hybrid manufacturing applications. Laser engineered net shaping (LENS), which was developed by Sandia National Labs, is one example of the powder-fed directed-energy deposition process for 3D printing or restoring metal parts.[147][148]

Metal wire processes

Laser-based wire-feed systems, such as laser metal deposition-wire (LMD-w), feed the wire through a nozzle that is melted by a laser using inert gas shielding in either an open environment (gas surrounding the laser) or in a sealed chamber. Electron beam freeform fabrication uses an electron beam heat source inside a vacuum chamber.

It is also possible to use conventional gas metal arc welding attached to a 3D stage to 3-D print metals such as steel, bronze and aluminium.[149][150] Low-cost open source RepRap-style 3-D printers have been outfitted with Arduino-based sensors and demonstrated reasonable metallurgical properties from conventional welding wire as feedstock.[151]

Selective powder deposition (SPD)

In selective powder deposition, build and support powders are selectively deposited into a crucible, such that the build powder takes the shape of the desired object and support powder fills the rest of the volume in the crucible. Then an infill material is applied, such that it comes in contact with the build powder. Then the crucible is fired up in a kiln at the temperature above the melting point of the infill but below the melting points of the powders. When the infill melts, it soaks the build powder. But it does not soak the support powder, because the support powder is chosen to be such that it is not wettable by the infill. If at the firing temperature, the atoms of the infill material and the build powder are mutually defusable, such as in the case of copper powder and zinc infill, then the resulting material will be a uniform mixture of those atoms, in this case, bronze. But if the atoms are not mutually defusable, such as in the case of tungsten and copper at 1100 °C, then the resulting material will be a composite. To prevent shape distortion, the firing temperature must be below the solidus temperature of the resulting alloy.[152]

Cryogenic 3D printing

Cryogenic 3D printing is a collection of techniques that forms solid structures by freezing liquid materials while they are deposited. As each liquid layer is applied, it is cooled by the low temperature of the previous layer and printing environment which results in solidification. Unlike other 3D printing techniques, cryogenic 3D printing requires a controlled printing environment. The ambient temperature must be below the material's freezing point to ensure the structure remains solid during manufacturing and the humidity must remain low to prevent frost formation between the application of layers.[153] Materials typically include water and water-based solutions, such as brine, slurry, and hydrogels.[154][155] Cryogenic 3D printing techniques include rapid freezing prototype (RFP),[154] low-temperature deposition manufacturing (LDM),[156] and freeze-form extrusion fabrication (FEF).[157]


Main article: Applications of 3D printing

This section may benefit from being shortened by the use of summary style. Summary style may involve the splitting of sections of text to one or more sub-topic articles which are then summarized in the main article.
The Audi RSQ was made with rapid prototyping industrial KUKA robots

3D printing or additive manufacturing has been used in manufacturing, medical, industry and sociocultural sectors (e.g. cultural heritage) to create successful commercial technology.[158] More recently, 3D printing has also been used in the humanitarian and development sector to produce a range of medical items, prosthetics, spares and repairs.[159] The earliest application of additive manufacturing was on the toolroom end of the manufacturing spectrum. For example, rapid prototyping was one of the earliest additive variants, and its mission was to reduce the lead time and cost of developing prototypes of new parts and devices, which was earlier only done with subtractive toolroom methods such as CNC milling, turning, and precision grinding.[160] In the 2010s, additive manufacturing entered production to a much greater extent.


Additive manufacturing of food is being developed by squeezing out food, layer by layer, into three-dimensional objects. A large variety of foods are appropriate candidates, such as chocolate and candy, and flat foods such as crackers, pasta,[161] and pizza.[162][163] NASA is looking into the technology in order to create 3D printed food to limit food waste and to make food that is designed to fit an astronaut's dietary needs.[164] In 2018, Italian bioengineer Giuseppe Scionti developed a technology allowing the production of fibrous plant-based meat analogues using a custom 3D bioprinter, mimicking meat texture and nutritional values.[165][166]


3D printed necklace

3D printing has entered the world of clothing, with fashion designers experimenting with 3D-printed bikinis, shoes, and dresses.[167] In commercial production, Nike used 3D printing to prototype and manufacture the 2012 Vapor Laser Talon football shoe for players of American football, and New Balance has 3D manufactured custom-fit shoes for athletes.[167][168] 3D printing has come to the point where companies are printing consumer-grade eyewear with on-demand custom fit and styling (although they cannot print the lenses). On-demand customization of glasses is possible with rapid prototyping.[169]


A 3D printed jet engine model

In cars, trucks, and aircraft, additive manufacturing is beginning to transform both unibody and fuselage design and production, and powertrain design and production. For example, General Electric uses high-end 3D printers to build parts for turbines.[170] Many of these systems are used for rapid prototyping before mass production methods are employed. Other prominent examples include:


AM's impact on firearms involves two dimensions: new manufacturing methods for established companies, and new possibilities for the making of do-it-yourself firearms. In 2012, the US-based group Defense Distributed disclosed plans to design a working plastic 3D printed firearm "that could be downloaded and reproduced by anybody with a 3D printer".[179][180] After Defense Distributed released their plans, questions were raised regarding the effects that 3D printing and widespread consumer-level CNC machining[181][182] may have on gun control effectiveness.[183][184][185][186] Moreover, armor-design strategies can be enhanced by taking inspiration from nature and prototyping those designs easily, using AM.[187]


Surgical uses of 3D printing-centric therapies began in the mid-1990s with anatomical modeling for bony reconstructive surgery planning. Patient-matched implants were a natural extension of this work, leading to truly personalized implants that fit one unique individual.[188] Virtual planning of surgery and guidance using 3D printed, personalized instruments have been applied to many areas of surgery including total joint replacement and craniomaxillofacial reconstruction with great success.[189][190] One example of this is the bioresorbable trachial splint to treat newborns with tracheobronchomalacia[191] developed at the University of Michigan. The use of additive manufacturing for serialized production of orthopedic implants (metals) is also increasing due to the ability to efficiently create porous surface structures that facilitate osseointegration. The hearing aid and dental industries are expected to be the biggest areas of future development using custom 3D printing technology.[192]

3D printing is not just limited to inorganic materials; there have been a number of biomedical advancements made possible by 3D printing. As of 2012, 3D bio-printing technology has been studied by biotechnology firms and academia for possible use in tissue engineering applications in which organs and body parts are built using inkjet printing techniques. In this process, layers of living cells are deposited onto a gel medium or sugar matrix and slowly built up to form three-dimensional structures including vascular systems.[193] 3D printing has been considered as a method of implanting stem cells capable of generating new tissues and organs in living humans.[194] In 2018, 3D printing technology was used for the first time to create a matrix for cell immobilization in fermentation. Propionic acid production by Propionibacterium acidipropionici immobilized on 3D-printed nylon beads was chosen as a model study. It was shown that those 3D-printed beads were capable of promoting high-density cell attachment and propionic acid production, which could be adapted to other fermentation bioprocesses.[195]

3D printing has also been employed by researchers in the pharmaceutical field. During the last few years, there has been a surge in academic interest regarding drug delivery with the aid of AM techniques. This technology offers a unique way for materials to be utilized in novel formulations.[196] AM manufacturing allows for the usage of materials and compounds in the development of formulations, in ways that are not possible with conventional/traditional techniques in the pharmaceutical field, e.g. tableting, cast-molding, etc. Moreover, one of the major advantages of 3D printing, especially in the case of fused deposition modelling (FDM), is the personalization of the dosage form that can be achieved, thus, targeting the patient's specific needs.[197] In the not-so-distant future, 3D printers are expected to reach hospitals and pharmacies in order to provide on-demand production of personalized formulations according to the patients' needs.[198]

3D printing has also been used for medical equipment. During the COVID-19 pandemic 3D printers were used to supplement the strained supply of PPE through volunteers using their personally owned printers to produce various pieces of personal protective equipment (i.e. frames for face shields).


3D printing, and open source 3D printers, in particular, are the latest technologies making inroads into the classroom.[199][200][201] Higher education has proven to be a major buyer of desktop and professional 3D printers which industry experts generally view as a positive indicator.[202] Some authors have claimed that 3D printers offer an unprecedented "revolution" in STEM education.[203][204] The evidence for such claims comes from both the low-cost ability for rapid prototyping in the classroom by students, but also the fabrication of low-cost high-quality scientific equipment from open hardware designs forming open-source labs.[205] Additionally, Libraries around the world have also become locations to house smaller 3D printers for educational and community access.[206] Future applications for 3D printing might include creating open-source scientific equipment.[205][207]

3D printed sculpture of an Egyptian pharaoh shown at Threeding

Replicating archeological artifacts

In the 2010s, 3D printing became intensively used in the cultural heritage field for preservation, restoration and dissemination purposes.[208] Many Europeans and North American Museums have purchased 3D printers and actively recreate missing pieces of their relics[209] and archaeological monuments such as Tiwanaku in Bolivia.[210] The Metropolitan Museum of Art and the British Museum have started using their 3D printers to create museum souvenirs that are available in the museum shops.[211] Other museums, like the National Museum of Military History and Varna Historical Museum, have gone further and sell through the online platform Threeding digital models of their artifacts, created using Artec 3D scanners, in 3D printing friendly file format, which everyone can 3D print at home.[212] Morehshin Allahyari, an Iranian-born U.S. artist, considers her use of 3D sculpting processes of re-constructing Iranian cultural treasures as feminist activism. Allahyari uses a 3D modeling software to reconstruct a series of cultural artifacts that were demolished by ISIS militants in 2014.[213]

Replicating historic buildings

The Stoofbrug [nl] in Amsterdam, the world's first 3D-printed metal bridge[98]

The application of 3D printing for the representation of architectural assets has many challenges. In 2018, the structure of Iran National Bank was traditionally surveyed and modeled in computer graphics software (specifically, Cinema4D) and was optimized for 3D printing. The team tested the technique for the construction of the part and it was successful. After testing the procedure, the modellers reconstructed the structure in Cinema4D and exported the front part of the model to Netfabb. The entrance of the building was chosen due to the 3D printing limitations and the budget of the project for producing the maquette. 3D printing was only one of the capabilities enabled by the produced 3D model of the bank, but due to the project's limited scope, the team did not continue modelling for the virtual representation or other applications.[214] In 2021, Parsinejad et al. comprehensively compared the hand surveying method for 3D reconstruction ready for 3D printing with digital recording (adoption of photogrammetry method).[214]

Soft actuators

3D printed soft actuators is a growing application of 3D printing technology that has found its place in the 3D printing applications. These soft actuators are being developed to deal with soft structures and organs, especially in biomedical sectors and where the interaction between humans and robots is inevitable. The majority of the existing soft actuators are fabricated by conventional methods that require manual fabrication of devices, post-processing/assembly, and lengthy iterations until the maturity of the fabrication is achieved. Instead of the tedious and time-consuming aspects of the current fabrication processes, researchers are exploring an appropriate manufacturing approach for the effective fabrication of soft actuators. Thus, 3D-printed soft actuators are introduced to revolutionize the design and fabrication of soft actuators with custom geometrical, functional, and control properties in a faster and inexpensive approach. They also enable incorporation of all actuator components into a single structure eliminating the need to use external joints, adhesives, and fasteners.

Circuit boards

Circuit board manufacturing involves multiple steps which include imaging, drilling, plating, solder mask coating, nomenclature printing and surface finishes. These steps include many chemicals such as harsh solvents and acids. 3D printing circuit boards remove the need for many of these steps while still producing complex designs.[215] Polymer ink is used to create the layers of the build while silver polymer is used for creating the traces and holes used to allow electricity to flow.[216] Current circuit board manufacturing can be a tedious process depending on the design. Specified materials are gathered and sent into inner layer processing where images are printed, developed and etched. The etch cores are typically punched to add lamination tooling. The cores are then prepared for lamination. The stack-up, the buildup of a circuit board, is built and sent into lamination where the layers are bonded. The boards are then measured and drilled. Many steps may differ from this stage however for simple designs, the material goes through a plating process to plate the holes and surface. The outer image is then printed, developed and etched. After the image is defined, the material must get coated with a solder mask for later soldering. Nomenclature is then added so components can be identified later. Then the surface finish is added. The boards are routed out of panel form into their singular or array form and then electrically tested. Aside from the paperwork that must be completed which proves the boards meet specifications, the boards are then packed and shipped. The benefits of 3D printing would be that the final outline is defined from the beginning, no imaging, punching or lamination is required and electrical connections are made with the silver polymer which eliminates drilling and plating. The final paperwork would also be greatly reduced due to the lack of materials required to build the circuit board. Complex designs which may take weeks to complete through normal processing can be 3D printed, greatly reducing manufacturing time.

A 3D selfie in 1:20 scale printed using gypsum-based printing


In 2005, academic journals began to report on the possible artistic applications of 3D printing technology.[217] Off-the-shelf machines were increasingly capable of producing practical household applications, for example, ornamental objects. Some practical examples include a working clock[218] and gears printed for home woodworking machines among other purposes.[219] Websites associated with home 3D printing tended to include backscratchers, coat hooks, door knobs, etc.[220] As of 2017, domestic 3D printing was reaching a consumer audience beyond hobbyists and enthusiasts. Several projects and companies are making efforts to develop affordable 3D printers for home desktop use. Much of this work has been driven by and targeted at DIY/maker/enthusiast/early adopter communities, with additional ties to the academic and hacker communities.

Sped on by decreases in price and increases in quality, As of 2019 an estimated 2 million people worldwide have purchased a 3D printer for hobby use.[221]

Legal aspects

Intellectual property

See also: Free hardware

3D printing has existed for decades within certain manufacturing industries where many legal regimes, including patents, industrial design rights, copyrights, and trademarks may apply. However, there is not much jurisprudence to say how these laws will apply if 3D printers become mainstream and individuals or hobbyist communities begin manufacturing items for personal use, for non-profit distribution, or for sale.

Any of the mentioned legal regimes may prohibit the distribution of the designs used in 3D printing or the distribution or sale of the printed item. To be allowed to do these things, where active intellectual property was involved, a person would have to contact the owner and ask for a licence, which may come with conditions and a price. However, many patent, design and copyright laws contain a standard limitation or exception for "private" or "non-commercial" use of inventions, designs or works of art protected under intellectual property (IP). That standard limitation or exception may leave such private, non-commercial uses outside the scope of IP rights.

Patents cover inventions including processes, machines, manufacturing, and compositions of matter and have a finite duration which varies between countries, but generally 20 years from the date of application. Therefore, if a type of wheel is patented, printing, using, or selling such a wheel could be an infringement of the patent.[222]

Copyright covers an expression[223] in a tangible, fixed medium and often lasts for the life of the author plus 70 years thereafter.[224] For example, a sculptor retains copyright over a statue, such that other people cannot then legally distribute designs to print an identical or similar statue without paying royalties, waiting for the copyright to expire, or working within a fair use exception.

When a feature has both artistic (copyrightable) and functional (patentable) merits when the question has appeared in US court, the courts have often held the feature is not copyrightable unless it can be separated from the functional aspects of the item.[224] In other countries the law and the courts may apply a different approach allowing, for example, the design of a useful device to be registered (as a whole) as an industrial design on the understanding that, in case of unauthorized copying, only the non-functional features may be claimed under design law whereas any technical features could only be claimed if covered by a valid patent.

Gun legislation and administration

Main article: 3D printed firearms

The US Department of Homeland Security and the Joint Regional Intelligence Center released a memo stating that "significant advances in three-dimensional (3D) printing capabilities, availability of free digital 3D printable files for firearms components, and difficulty regulating file sharing may present public safety risks from unqualified gun seekers who obtain or manufacture 3D printed guns" and that "proposed legislation to ban 3D printing of weapons may deter, but cannot completely prevent their production. Even if the practice is prohibited by new legislation, online distribution of these 3D printable files will be as difficult to control as any other illegally traded music, movie or software files."[225]

Attempting to restrict the distribution of gun plans via the Internet has been likened to the futility of preventing the widespread distribution of DeCSS, which enabled DVD ripping.[226][227][228][229] After the US government had Defense Distributed take down the plans, they were still widely available via the Pirate Bay and other file sharing sites.[230] Downloads of the plans from the UK, Germany, Spain, and Brazil were heavy.[231][232] Some US legislators have proposed regulations on 3D printers to prevent them from being used for printing guns.[233][234] 3D printing advocates have suggested that such regulations would be futile, could cripple the 3D printing industry and could infringe on free speech rights, with early pioneers of 3D printing professor Hod Lipson suggesting that gunpowder could be controlled instead.[235][236][237][238][239][240]

Internationally, where gun controls are generally stricter than in the United States, some commentators have said the impact may be more strongly felt since alternative firearms are not as easily obtainable.[241] Officials in the United Kingdom have noted that producing a 3D-printed gun would be illegal under their gun control laws.[242] Europol stated that criminals have access to other sources of weapons but noted that as technology improves, the risks of an effect would increase.[243][244]

Aerospace regulation

In the United States, the FAA has anticipated a desire to use additive manufacturing techniques and has been considering how best to regulate this process.[245] The FAA has jurisdiction over such fabrication because all aircraft parts must be made under FAA production approval or under other FAA regulatory categories.[246] In December 2016, the FAA approved the production of a 3D printed fuel nozzle for the GE LEAP engine.[247] Aviation attorney Jason Dickstein has suggested that additive manufacturing is merely a production method, and should be regulated like any other production method.[248][249] He has suggested that the FAA's focus should be on guidance to explain compliance, rather than on changing the existing rules, and that existing regulations and guidance permit a company "to develop a robust quality system that adequately reflects regulatory needs for quality assurance".[248]

Health and safety

Main article: Health and safety hazards of 3D printing

See also: Health and safety hazards of nanomaterials

A video on research done on printer emissions

Research on the health and safety concerns of 3D printing is new and in development due to the recent proliferation of 3D printing devices. In 2017, the European Agency for Safety and Health at Work published a discussion paper on the processes and materials involved in 3D printing, the potential implications of this technology for occupational safety and health and avenues for controlling potential hazards.[250]

Noise levels

Noise level is measured in decibels (dB), and can vary greatly in home printers from 15 dB to 75 dB.[251] Some main sources of noise in filament printers are fans, motors and bearings, while in resin printers the fans usually are responsible for most of the noise.[251] Some methods for dampening the noise from a printer may be to install vibration isolation, use larger diameter fans, perform regular maintenance and lubrication, or use a soundproofing enclosure.[251]


Additive manufacturing, starting with today's infancy period, requires manufacturing firms to be flexible, ever-improving users of all available technologies to remain competitive. Advocates of additive manufacturing also predict that this arc of technological development will counter globalization, as end users will do much of their own manufacturing rather than engage in trade to buy products from other people and corporations.[16] The real integration of the newer additive technologies into commercial production, however, is more a matter of complementing traditional subtractive methods rather than displacing them entirely.[252]

The futurologist Jeremy Rifkin[253] claimed that 3D printing signals the beginning of a third industrial revolution,[254] succeeding the production line assembly that dominated manufacturing starting in the late 19th century.

Social change

Street sign in Windhoek, Namibia, advertising 3D printing, July 2018

Since the 1950s, a number of writers and social commentators have speculated in some depth about the social and cultural changes that might result from the advent of commercially affordable additive manufacturing technology.[255] In recent years, 3D printing has created a significant impact in the humanitarian and development sector. Its potential to facilitate distributed manufacturing is resulting in supply chain and logistics benefits, by reducing the need for transportation, warehousing and wastage. Furthermore, social and economic development is being advanced through the creation of local production economies.[159]

Others have suggested that as more and more 3D printers start to enter people's homes, the conventional relationship between the home and the workplace might get further eroded.[256] Likewise, it has also been suggested that, as it becomes easier for businesses to transmit designs for new objects around the globe, so the need for high-speed freight services might also become less.[257] Finally, given the ease with which certain objects can now be replicated, it remains to be seen whether changes will be made to current copyright legislation so as to protect intellectual property rights with the new technology widely available.

Some call attention to the conjunction of commons-based peer production with 3D printing and other low-cost manufacturing techniques.[258][259][260] The self-reinforced fantasy of a system of eternal growth can be overcome with the development of economies of scope, and here, society can play an important role contributing to the raising of the whole productive structure to a higher plateau of more sustainable and customized productivity.[258] Further, it is true that many issues, problems, and threats arise due to the democratization of the means of production, and especially regarding the physical ones.[258] For instance, the recyclability of advanced nanomaterials is still questioned; weapons manufacturing could become easier; not to mention the implications for counterfeiting[261] and on intellectual property.[262] It might be maintained that in contrast to the industrial paradigm whose competitive dynamics were about economies of scale, commons-based peer production 3D printing could develop economies of scope. While the advantages of scale rest on cheap global transportation, the economies of scope share infrastructure costs (intangible and tangible productive resources), taking advantage of the capabilities of the fabrication tools.[258] And following Neil Gershenfeld[263] in that "some of the least developed parts of the world need some of the most advanced technologies", commons-based peer production and 3D printing may offer the necessary tools for thinking globally but acting locally in response to certain needs.

Larry Summers wrote about the "devastating consequences" of 3D printing and other technologies (robots, artificial intelligence, etc.) for those who perform routine tasks. In his view, "already there are more American men on disability insurance than doing production work in manufacturing. And the trends are all in the wrong direction, particularly for the less skilled, as the capacity of capital embodying artificial intelligence to replace white-collar as well as blue-collar work will increase rapidly in the years ahead." Summers recommends more vigorous cooperative efforts to address the "myriad devices" (e.g., tax havens, bank secrecy, money laundering, and regulatory arbitrage) enabling the holders of great wealth to "a paying" income and estate taxes, and to make it more difficult to accumulate great fortunes without requiring "great social contributions" in return, including: more vigorous enforcement of anti-monopoly laws, reductions in "excessive" protection for intellectual property, greater encouragement of profit-sharing schemes that may benefit workers and give them a stake in wealth accumulation, strengthening of collective bargaining arrangements, improvements in corporate governance, strengthening of financial regulation to eliminate subsidies to financial activity, easing of land-use restrictions that may cause the real estate of the rich to keep rising in value, better training for young people and retraining for displaced workers, and increased public and private investment in infrastructure development—e.g., in energy production and transportation.[264]

Michael Spence wrote that "Now comes a ... powerful, wave of digital technology that is replacing labor in increasingly complex tasks. This process of labor substitution and disintermediation has been underway for some time in service sectors—think of ATMs, online banking, enterprise resource planning, customer relationship management, mobile payment systems, and much more. This revolution is spreading to the production of goods, where robots and 3D printing are displacing labor." In his view, the vast majority of the cost of digital technologies comes at the start, in the design of hardware (e.g. 3D printers) and, more importantly, in creating the software that enables machines to carry out various tasks. "Once this is achieved, the marginal cost of the hardware is relatively low (and declines as scale rises), and the marginal cost of replicating the software is essentially zero. With a huge potential global market to amortize the upfront fixed costs of design and testing, the incentives to invest [in digital technologies] are compelling."[265]

Spence believes that, unlike prior digital technologies, which drove firms to deploy underutilized pools of valuable labor around the world, the motivating force in the current wave of digital technologies "is cost reduction via the replacement of labor". For example, as the cost of 3D printing technology declines, it is "easy to imagine" that production may become "extremely" local and customized. Moreover, production may occur in response to actual demand, not anticipated or forecast demand. Spence believes that labor, no matter how inexpensive, will become a less important asset for growth and employment expansion, with labor-intensive, process-oriented manufacturing becoming less effective, and that re-localization will appear in both developed and developing countries. In his view, production will not disappear, but it will be less labor-intensive, and all countries will eventually need to rebuild their growth models around digital technologies and the human capital supporting their deployment and expansion. Spence writes that "the world we are entering is one in which the most powerful global flows will be ideas and digital capital, not goods, services, and traditional capital. Adapting to this will require shifts in mindsets, policies, investments (especially in human capital), and quite possibly models of employment and distribution."[265]

Naomi Wu regards the usage of 3D printing in the Chinese classroom (where rote memorization is standard) to teach design principles and creativity as the most exciting recent development of the technology, and more generally regards 3D printing as being the next desktop publishing revolution.[266]

Environmental change

The growth of additive manufacturing could have a large impact on the environment. As opposed to traditional manufacturing, for instance, in which pieces are cut from larger blocks of material, additive manufacturing creates products layer-by-layer and prints only relevant parts, wasting much less material and thus wasting less energy in producing the raw materials needed.[267] By making only the bare structural necessities of products, additive manufacturing also could make a profound contribution to lightweighting, reducing the energy consumption and greenhouse gas emissions of vehicles and other forms of transportation.[268] A case study on an airplane component made using additive manufacturing, for example, found that the component's use saves 63% of relevant energy and carbon dioxide emissions over the course of the product's lifetime.[269] In addition, previous life-cycle assessment of additive manufacturing has estimated that adopting the technology could further lower carbon dioxide emissions since 3D printing creates localized production, and products would not need to be transported long distances to reach their final destination.[270]

Continuing to adopt additive manufacturing does pose some environmental downsides, however. Despite additive manufacturing reducing waste from the subtractive manufacturing process by up to 90%, the additive manufacturing process creates other forms of waste such as non-recyclable material (metal) powders. Additive manufacturing has not yet reached its theoretical material efficiency potential of 97%, but it may get closer as the technology continues to increase productivity.[271]

Some large FDM printers that melt high-density polyethylene (HDPE) pellets may also accept sufficiently clean recycled material such as chipped milk bottles. In addition, these printers can use shredded material coming from faulty builds or unsuccessful prototype versions thus reducing overall project wastage and materials handling and storage. The concept has been explored in the RecycleBot.

See also


  1. ^ "3D printing scales up". The Economist. 5 September 2013. Archived from the original on 15 July 2019. Retrieved 15 July 2019.
  2. ^ Gao, Wei; Zhang, Yunbo; Ramanujan, Devarajan; Ramani, Karthik; Chen, Yong; Williams, Christopher B.; Wang, Charlie C. L.; Shin, Yung C.; Zhang, Song; Zavattieri, Pablo D. (2015). "The status, challenges, and future of additive manufacturing in engineering". Computer-Aided Design. 69: 65–89. doi:10.1016/j.cad.2015.04.001. S2CID 33086357.
  3. ^ Ngo, Tuan D.; Kashani, Alireza; Imbalzano, Gabriele; Nguyen, Kate T. Q.; Hui, David (2018). "Additive manufacturing (3D printing): A review of materials, methods, applications and challenges". Composites Part B: Engineering. 143: 172–196. doi:10.1016/j.compositesb.2018.02.012. S2CID 139464688.
  4. ^ Excell, Jon (23 May 2010). "The rise of additive manufacturing". The Engineer. Archived from the original on 19 September 2015. Retrieved 30 October 2013.
  5. ^ "Learning Course: Additive Manufacturing – Additive Fertigung". tmg-muenchen.de. Archived from the original on 23 August 2019. Retrieved 23 August 2019.
  6. ^ Lam, Hugo K.S.; Ding, Li; Cheng, T.C.E.; Zhou, Honggeng (1 January 2019). "The impact of 3D printing implementation on stock returns: A contingent dynamic capabilities perspective". International Journal of Operations & Production Management. 39 (6/7/8): 935–961. doi:10.1108/IJOPM-01-2019-0075. ISSN 0144-3577. S2CID 211386031.
  7. ^ "3D Printing: All You Need To Know". explainedideas.com. Archived from the original on 20 August 2022. Retrieved 11 August 2022.
  8. ^ a b "Most used 3D printing technologies 2017–2018 | Statistic". Statista. Archived from the original on 2 March 2019. Retrieved 2 December 2018.
  9. ^ "Google Ngram Viewer". books.google.com. Archived from the original on 6 July 2024. Retrieved 23 August 2019.
  10. ^ "ISO/ASTM 52900:2015 – Additive manufacturing – General principles – Terminology". iso.org. Archived from the original on 10 July 2017. Retrieved 15 June 2017.
  11. ^ a b Zelinski, Peter (4 August 2017), "Additive manufacturing and 3D printing are two different things", Additive Manufacturing, archived from the original on 12 August 2017, retrieved 11 August 2017.
  12. ^ M. Leinster, Things Pass By, in The Earth In Peril (D. Wollheim ed.). Ace Books 1957, USA, List of Ace SF double titles D-205, p.25, story copyright 1945, by Standard Magazines Inc.
  13. ^ "US3596285A - Liquid metal recorder". Google Patents. Archived from the original on 5 March 2024.
  14. ^ "Ariadne". New Scientist. 64 (917): 80. 3 October 1974. ISSN 0262-4079.[permanent dead link]
  15. ^ Ellam, Richard (26 February 2019). "3D printing: you read it here first". New Scientist. Archived from the original on 17 August 2019. Retrieved 23 August 2019.
  16. ^ a b Jane Bird (8 August 2012). "Exploring the 3D printing opportunity". Financial Times. Archived from the original on 16 January 2016. Retrieved 30 August 2012.
  17. ^ Hideo Kodama, " Background of my invention of 3D printer and its spread", Patent Magazine of Japan Patent Attorneys Association, vo.67, no.13, pp.109-118, November 2014.
  18. ^ JP-S56-144478, "JP Patent: S56-144478 - 3D figure production device", issued 10 November 1981 
  19. ^ Hideo Kodama, "A Scheme for Three-Dimensional Display by Automatic Fabrication of Three-Dimensional Model", IEICE Transactions on Electronics (Japanese Edition), vol. J64-C, No. 4, pp. 237–41, April 1981
  20. ^ Hideo Kodama, "Automatic method for fabricating a three-dimensional plastic model with photo-hardening polymer", Review of Scientific Instruments, Vol. 52, No. 11, pp. 1770–73, November 1981
  21. ^ 4665492, Masters, William E., "United States Patent: 4665492 - Computer automated manufacturing process and system", issued 12 May 1987  Archived 12 April 2022 at the Wayback Machine
  22. ^ "3-D Printing Steps into the Spotlight". Upstate Business Journal. 11 April 2013. Archived from the original on 20 December 2019. Retrieved 20 December 2019.
  23. ^ Wang, Ben (27 January 1999). Concurrent Design of Products, Manufacturing Processes and Systems. CRC Press. ISBN 978-90-5699-628-4.
  24. ^ Jean-Claude, Andre. "Disdpositif pour realiser un modele de piece industrielle". National De La Propriete Industrielle. Archived from the original on 5 February 2016. Retrieved 5 February 2016.
  25. ^ Mendoza, Hannah Rose (15 May 2015). "Alain Le Méhauté, The Man Who Submitted Patent For SLA 3D Printing Before Chuck Hull". 3dprint.com. Archived from the original on 3 February 2016. Retrieved 5 February 2016.
  26. ^ Moussion, Alexandre (2014). "Interview d'Alain Le Méhauté, l'un des pères de l'impression (Interview of Alain Le Mehaute, one of the 3D printinf technologies fathers) 3D". Primante 3D.
  27. ^ a b Howard, Robert (2009). Connecting the dots: my life and inventions, from X-rays to death rays. New York, NY: Welcome Rain. pp. 195–197. ISBN 978-1-56649-957-6. OCLC 455879561.
  28. ^ a b c d Barnatt, Christopher (2013). 3D printing: the next industrial revolution. [Nottingham, England?]: ExplainingTheFuture.com. ISBN 978-1-4841-8176-8. OCLC 854672031.
  29. ^ "3D Printing: What You Need to Know". PCMag.com. Archived from the original on 18 October 2013. Retrieved 30 October 2013.
  30. ^ Apparatus for Production of Three-Dimensional Objects by Stereolithography (8 August 1984)
  31. ^ Freedman, David H (2012). "Layer By Layer". Technology Review. 115 (1): 50–53.
  32. ^ "History of 3D Printing: When Was 3D Printing Invented?". All3DP. 10 December 2018. Archived from the original on 3 July 2019. Retrieved 22 November 2019.
  33. ^ "The Evolution of 3D Printing: Past, Present and Future". 3D Printing Industry. 1 August 2016. Archived from the original on 17 March 2021. Retrieved 24 February 2021.
  34. ^ Amon, C. H.; Beuth, J. L.; Weiss, L. E.; Merz, R.; Prinz, F. B. (1998). "Shape Deposition Manufacturing With Microcasting: Processing, Thermal and Mechanical Issues". Journal of Manufacturing Science and Engineering. 120 (3): 656–665. doi:10.1115/1.2830171. Archived from the original (PDF) on 20 December 2014. Retrieved 20 December 2014.
  35. ^ Beck, J.E.; Fritz, B.; Siewiorek, Daniel; Weiss, Lee (1992). "Manufacturing Mechatronics Using Thermal Spray Shape Deposition" (PDF). Proceedings of the 1992 Solid Freeform Fabrication Symposium. Archived from the original (PDF) on 24 December 2014. Retrieved 20 December 2014.
  36. ^ Prinz, F. B.; Merz, R.; Weiss, Lee (1997). Ikawa, N. (ed.). Building Parts You Could Not Build Before. Proceedings of the 8th International Conference on Production Engineering. London, UK: Chapman & Hall. pp. 40–44.
  37. ^ Wu, Peng; Wang, Jun; Wang, Xiangyu (1 August 2016). "A critical review of the use of 3-D printing in the construction industry". Automation in Construction. 68: 21–31. doi:10.1016/j.autcon.2016.04.005. hdl:20.500.11937/7988. ISSN 0926-5805. S2CID 54037889.
  38. ^ "About - RepRap". reprap.org. Archived from the original on 27 December 2023. Retrieved 27 November 2023.
  39. ^ Malone, Evan; Lipson, Hod (1 January 2007). "Fab@Home: the personal desktop fabricator kit". Rapid Prototyping Journal. 13 (4): 245–255. doi:10.1108/13552540710776197. ISSN 1355-2546.
  40. ^ Matias, Elizabeth; Rao, Bharat (2015). "3D printing: On its historical evolution and the implications for business". 2015 Portland International Conference on Management of Engineering and Technology (PICMET). pp. 551–558. doi:10.1109/PICMET.2015.7273052. ISBN 978-1-8908-4331-1. S2CID 10569154. Archived from the original on 25 January 2024. Retrieved 29 November 2023.
  41. ^ GE jet engine bracket challenge, archived from the original on 7 November 2020, retrieved 7 June 2014
  42. ^ Zelinski, Peter (2 June 2014), "How do you make a howitzer less heavy?", Modern Machine Shop, archived from the original on 15 November 2020, retrieved 7 June 2014
  43. ^ "As Billions More Fly, Here's How Aviation Could Evolve". National Geographic. 22 June 2017. Archived from the original on 27 February 2021. Retrieved 20 November 2020.
  44. ^ "Aviation and Aerospace Industry". GE Additive. Archived from the original on 17 January 2021. Retrieved 20 November 2020.
  45. ^ "Pratt & Whitney to Deliver First Entry Into Service Engine Parts Using Additive Manufacturing". Additive Manufacturing. 6 April 2015. Archived from the original on 19 October 2020. Retrieved 20 December 2020.
  46. ^ Han, Pinlina (2017). "Additive Design and Manufacturing of Jet Engine Parts". Engineering. 3 (5): 648–652. Bibcode:2017Engin...3..648H. doi:10.1016/j.eng.2017.05.017.
  47. ^ b. Mtaho, Adam; r.Ishengoma, Fredrick (2014). "3D Printing: Developing Countries Perspectives". International Journal of Computer Applications. 104 (11): 30. arXiv:1410.5349. Bibcode:2014IJCA..104k..30R. doi:10.5120/18249-9329. S2CID 5381455.
  48. ^ "Filabot: Plastic Filament Maker". Kickstarter. 24 May 2012. Retrieved 1 December 2018.
  49. ^ Cook, Benjamin Stassen (26 March 2014). "VIPRE 3D Printed Electronics". Archived from the original on 2 April 2019. Retrieved 2 April 2019.
  50. ^ "3D Printer Price: How Much Does a 3D Printer Cost?". 3D Insider. 22 June 2017. Archived from the original on 27 January 2021. Retrieved 24 February 2021.
  51. ^ "How Much Does a 3D Printer Cost? Calculate the ROI Now". Formlabs. Archived from the original on 16 January 2021. Retrieved 24 February 2021.
  52. ^ "Patient receives the world's first fully 3D-printed prosthetic eye". Engadget. 30 November 2021. Archived from the original on 4 December 2021. Retrieved 4 December 2021.
  53. ^ "Vsak dan prvi - 24ur.com". www.24ur.com. Retrieved 4 December 2021.
  54. ^ "World's biggest 3D printer whirs into action". www.bbc.com. Archived from the original on 26 April 2024. Retrieved 26 April 2024.
  55. ^ University of Illinois at Urbana-Champaign (25 May 2024). "Synthetic Bones Designed by AI Set to Transform Orthopedic Surgery". SciTechDaily. Archived from the original on 26 May 2024. Retrieved 26 May 2024.
  56. ^ Salas, Joe (23 May 2024). "Autonomous robot invents the world's best shock absorber". New Atlas. Archived from the original on 26 May 2024. Retrieved 26 May 2024.
  57. ^ Weller, Christian; Kleer, Robin; Piller, Frank T. (1 June 2015). "Economic implications of 3D printing: Market structure models in light of additive manufacturing revisited". International Journal of Production Economics. 164: 43–56. doi:10.1016/j.ijpe.2015.02.020. ISSN 0925-5273. Archived from the original on 9 July 2019. Retrieved 27 March 2024.
  58. ^ Ben-Ner, Avner; Siemsen, Enno (February 2017). "Decentralization and Localization of Production: The Organizational and Economic Consequences of Additive Manufacturing (3D Printing)". California Management Review. 59 (2): 5–23. doi:10.1177/0008125617695284. ISSN 0008-1256. Archived from the original on 27 March 2024. Retrieved 27 March 2024.
  59. ^ Li, Zhaolong; Wang, Qinghai; Liu, Guangdong (April 2022). "A Review of 3D Printed Bone Implants". Micromachines. 13 (4): 528. doi:10.3390/mi13040528. ISSN 2072-666X. PMC 9025296. PMID 35457833.
  60. ^ P. Sivasankaran and B. Radjaram, "3D Printing and Its Importance in Engineering - A Review", 2020 International Conference on System, Computation, Automation and Networking (ICSCAN), Pondicherry, India, 2020, pp. 1-3, doi:10.1109/ICSCAN49426.2020.9262378.
  61. ^ Zhang, Zhi; Zhang, Lei; Song, Bo; Yao, Yonggang; Shi, Yusheng (1 March 2022). "Bamboo-inspired, simulation-guided design and 3D printing of light-weight and high-strength mechanical metamaterials". Applied Materials Today. 26: 101268. doi:10.1016/j.apmt.2021.101268. ISSN 2352-9407.
  62. ^ Westerweel, Bram; Basten, Rob; denBoer, Jelmar; vanHoutum, Geert-Jan (June 2021). "Printing Spare Parts at Remote Locations: Fulfilling the Promise of Additive Manufacturing". Production and Operations Management. 30 (6): 1615–1632. doi:10.1111/poms.13298. ISSN 1059-1478. Archived from the original on 27 March 2024. Retrieved 27 March 2024.
  63. ^ Manero, Albert; Smith, Peter; Sparkman, John; Dombrowski, Matt; Courbin, Dominique; Kester, Anna; Womack, Isaac; Chi, Albert (January 2019). "Implementation of 3D Printing Technology in the Field of Prosthetics: Past, Present, and Future". International Journal of Environmental Research and Public Health. 16 (9): 1641. doi:10.3390/ijerph16091641. ISSN 1660-4601. PMC 6540178. PMID 31083479.
  64. ^ Caprioli, Matteo; Roppolo, Ignazio; Chiappone, Annalisa; Larush, Liraz; Pirri, Candido Fabrizio; Magdassi, Shlomo (28 April 2021). "3D-printed self-healing hydrogels via Digital Light Processing". Nature Communications. 12 (1): 2462. Bibcode:2021NatCo..12.2462C. doi:10.1038/s41467-021-22802-z. ISSN 2041-1723. PMC 8080574. PMID 33911075.
  65. ^ Nachal, N.; Moses, J. A.; Karthik, P.; Anandharamakrishnan, C. (1 September 2019). "Applications of 3D Printing in Food Processing". Food Engineering Reviews. 11 (3): 123–141. doi:10.1007/s12393-019-09199-8. ISSN 1866-7929.
  66. ^ Zastrow, Mark (5 February 2020). "3D printing gets bigger, faster and stronger". Nature. 578 (7793): 20–23. Bibcode:2020Natur.578...20Z. doi:10.1038/d41586-020-00271-6. ISSN 0028-0836. PMID 32025009.
  67. ^ Schubert, Carl; Langeveld, Mark C. van; Donoso, Larry A. (1 February 2014). "Innovations in 3D printing: a 3D overview from optics to organs". British Journal of Ophthalmology. 98 (2): 159–161. doi:10.1136/bjophthalmol-2013-304446. ISSN 0007-1161. PMID 24288392. Archived from the original on 27 March 2024. Retrieved 27 March 2024.
  68. ^ K. J. A. Al Ahbabi, M. M. S. Alrashdi and W. K. Ahmed, "The Capabilities of 3D Printing Technology in the Production of Battery Energy Storage System", 2021 6th International Conference on Renewable Energy: Generation and Applications (ICREGA), Al Ain, United Arab Emirates, 2021, pp. 211-216, doi:10.1109/ICREGA50506.2021.9388302.
  69. ^ F. Auricchio, "The magic world of 3D printing", 2017 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications (IMWS-AMP), Pavia, Italy, 2017, pp. 1-1, doi:10.1109/IMWS-AMP.2017.8247328.
  70. ^ Attaran, Mohsen (2017). "The rise of 3-D printing: The advantages of additive manufacturing over traditional manufacturing". Business Horizons. 60 (5): 677–688. doi:10.1016/j.bushor.2017.05.011.
  71. ^ Jacobs, Paul Francis (1 January 1992). Rapid Prototyping & Manufacturing: Fundamentals of Stereolithography. Society of Manufacturing Engineers. ISBN 978-0-87263-425-1.
  72. ^ Azman, Abdul Hadi; Vignat, Frédéric; Villeneuve, François (29 April 2018). "Cad Tools and File Format Performance Evaluation in Designing Lattice Structures for Additive Manufacturing". Jurnal Teknologi. 80 (4). doi:10.11113/jt.v80.12058. ISSN 2180-3722.
  73. ^ "3D solid repair software – Fix STL polygon mesh files – LimitState:FIX". Print.limitstate.com. Archived from the original on 4 March 2016. Retrieved 4 January 2016.
  74. ^ "3D Printing Pens". yellowgurl.com. Archived from the original on 16 September 2016. Retrieved 9 August 2016.
  75. ^ "Model Repair Service". Modelrepair.azurewebsites.net. Archived from the original on 4 March 2016. Retrieved 4 January 2016.
  76. ^ "3D Printing Overhang: How to 3D Print Overhangs". All3DP. 16 June 2021. Archived from the original on 9 October 2021. Retrieved 11 October 2021.
  77. ^ "Magics, the Most Powerful 3D Printing Software | Software for additive manufacturing". Software.materialise.com. Archived from the original on 4 January 2016. Retrieved 4 January 2016.
  78. ^ "netfabb Cloud Services". Netfabb.com. 15 May 2009. Archived from the original on 30 December 2015. Retrieved 4 January 2016.
  79. ^ "How to repair a 3D scan for printing". Anamarva.com. Archived from the original on 24 January 2016. Retrieved 4 January 2016.
  80. ^ Fausto Bernardini, Holly E. Rushmeier (2002). "The 3D Model Acquisition Pipeline GAS" (PDF). Computer Graphics Forum. 21 (2): 149–72. doi:10.1111/1467-8659.00574. S2CID 15779281. Archived (PDF) from the original on 3 March 2016. Retrieved 4 January 2016.
  81. ^ Satyanarayana, B.; Prakash, Kode Jaya (2015). "Component Replication Using 3D Printing Technology". Procedia Materials Science. 10. Elsevier BV: 263–269. doi:10.1016/j.mspro.2015.06.049. ISSN 2211-8128.
  82. ^ "Objet Connex 3D Printers". Objet Printer Solutions. Archived from the original on 7 November 2011. Retrieved 31 January 2012.
  83. ^ Lee, Handol; Kwak, Dong-Bin; Choi, Chi Young; Ahn, Kang-Ho (2023). "Accurate measurements of particle emissions from a three-dimensional printer using a chamber test with a mixer-installed sampling system". Scientific Reports. 13 (1): 6495. Bibcode:2023NatSR..13.6495L. doi:10.1038/s41598-023-33538-9. PMC 10119104. PMID 37081153. 6495.
  84. ^ "Design Guide: Preparing a File for 3D Printing" (PDF). Xometry. Archived (PDF) from the original on 20 January 2018. Retrieved 19 January 2018.
  85. ^ "How to Smooth 3D-Printed Parts". Machine Design. 29 April 2014. Archived from the original on 29 November 2020. Retrieved 23 August 2019.
  86. ^ Kraft, Caleb. "Smoothing Out Your 3D Prints With Acetone Vapor". Make. Archived from the original on 24 March 2016. Retrieved 5 January 2016.
  87. ^ Hart, Kevin R.; Dunn, Ryan M.; Sietins, Jennifer M.; Hofmeister Mock, Clara M.; Mackay, Michael E.; Wetzel, Eric D. (2018). "Increased fracture toughness of additively manufactured amorphous thermoplastics via thermal annealing". Polymer. 144: 192–204. doi:10.1016/j.polymer.2018.04.024. ISSN 0032-3861.
  88. ^ Valvez, S.; Silva, A.P.; Reis, P.N.B.; Berto, F. (2022). "Annealing effect on mechanical properties of 3D printed composites". Procedia Structural Integrity. 37: 738–745. doi:10.1016/j.prostr.2022.02.004. ISSN 2452-3216.
  89. ^ a b Benwood, C.; Anstey, A.; Andrzejewski, J.; Misra, M.; Mohanty, A. K. (2018). "Improving the Impact Strength and Heat Resistance of 3D Printed Models: Structure, Property, and Processing Correlationships during Fused Deposition Modeling (FDM) of Poly(Lactic Acid)". ACS Omega. 3 (4): 4400–4411. doi:10.1021/acsomega.8b00129. PMC 6641607. PMID 31458666.
  90. ^ Wijnbergen, D.C.; van der Stelt, M.; Verhamme, L.M. (2021). "The effect of annealing on deformation and mechanical strength of tough PLA and its application in 3D printed prosthetic sockets". Rapid Prototyping Journal. 27 (11): 81–89. doi:10.1108/RPJ-04-2021-0090. S2CID 244259184.
  91. ^ Wei Du; Qian Bai; Bi Zhang (2016). "A Novel Method for Additive/Subtractive Hybrid Manufacturing of Metallic Parts". Procedia Manufacturing. 5: 1018–1030. doi:10.1016/j.promfg.2016.08.067. ISSN 2351-9789.
  92. ^ Li F, Chen S, Shi J, Tian H (2018). "Investigation on Surface Quality in a Hybrid Manufacturing System Combining Wire and Arc Additive Manufacturing and Machining". In Chen S, Zhang Y, Feng Z (eds.). Transactions on Intelligent Welding Manufacturing. Springer. pp. 127–137. doi:10.1007/978-981-10-7043-3_9. ISBN 978-981-10-7042-6.
  93. ^ Delfs, P.; T̈ows, M.; Schmid, H.-J. (October 2016). "Optimized build orientation of additive manufactured parts for improved surface quality and build time". Additive Manufacturing. 12: 314–320. doi:10.1016/j.addma.2016.06.003. ISSN 2214-8604.
  94. ^ O'Connell, Jackson (29 April 2022). "Cura Adaptive Layers – Simply Explained". All3DP. Archived from the original on 29 March 2023. Retrieved 29 March 2023.
  95. ^ Boissonneault, Tess (15 August 2022). "Your Guide to Painting PLA 3D Prints". Wevolver. Archived from the original on 29 March 2023. Retrieved 29 March 2023.
  96. ^ Haselhuhn, Amberlee S.; Gooding, Eli J.; Glover, Alexandra G.; Anzalone, Gerald C.; Wijnen, Bas; Sanders, Paul G.; Pearce, Joshua M. (2014). "Substrate Release Mechanisms for Gas Metal Arc Weld 3D Aluminum Metal Printing". 3D Printing and Additive Manufacturing. 1 (4): 204. doi:10.1089/3dp.2014.0015. S2CID 135499443.
  97. ^ Haselhuhn, Amberlee S.; Wijnen, Bas; Anzalone, Gerald C.; Sanders, Paul G.; Pearce, Joshua M. (2015). "In situ formation of substrate release mechanisms for gas metal arc weld metal 3-D printing". Journal of Materials Processing Technology. 226: 50. doi:10.1016/j.jmatprotec.2015.06.038. Archived from the original on 28 April 2019. Retrieved 19 July 2019.
  98. ^ a b Huet, Natalie (16 July 2021). "Amsterdam unveils the world's first 3D-printed steel bridge". euronews.
  99. ^ Wang, Xin; Jiang, Man; Zhou, Zuowan; Gou, Jihua; Hui, David (2017). "3D printing of polymer matrix composites: A review and prospective". Composites Part B: Engineering. 110: 442–458. doi:10.1016/j.compositesb.2016.11.034.
  100. ^ Rose, L. (2011). On the degradation of porous stainless steel (Thesis). University of British Columbia. pp. 104–143. doi:10.14288/1.0071732.
  101. ^ Zadi-Maad, Ahmad; Rohbib, Rohbib; Irawan, A (2018). "Additive manufacturing for steels: a review". IOP Conference Series: Materials Science and Engineering. 285 (1): 012028. Bibcode:2018MS&E..285a2028Z. doi:10.1088/1757-899X/285/1/012028.
  102. ^ Galante, Raquel; G. Figueiredo-Pina, Celio; Serro, Ana Paula (2019). "Additive manufacturing of ceramics for dental applications". Dental Materials. 35 (6): 825–846. doi:10.1016/j.dental.2019.02.026. PMID 30948230. S2CID 96434269.
  103. ^ Cooper, Kenneth G. (2001). Rapid prototyping technology: selection and application. New York: Marcel Dekker. pp. 39–41. ISBN 0-8247-0261-1. OCLC 45873626.
  104. ^ a b Burns, Marshall (1993). Automated fabrication: improving productivity in manufacturing. Englewood Cliffs, N.J.: PTR Prentice Hall. pp. 8, 15, 49, 95, 97. ISBN 0-13-119462-3. OCLC 27810960.
  105. ^ Mici, Joni; Ko, Jang Won; West, Jared; Jaquith, Jeffrey; Lipson, Hod (2019). "Parallel electrostatic grippers for layered assembly". Additive Manufacturing. 27: 451–460. doi:10.1016/j.addma.2019.03.032. S2CID 141154762.
  106. ^ Spec2Fab: A reducer-tuner model for translating specifications to 3D prints. Spec2Fab. CiteSeerX
  107. ^ Researchers Turn to Multi-Material 3D Printing to Develop Responsive, Versatile Smart Composites. Researchers Turn to Multi-Material 3D Printing to Develop Responsive, Versatile Smart Composites. Archived from the original on 20 February 2019. Retrieved 19 February 2019.
  108. ^ CIMP-3D. CIMP-3d (in Chinese). Archived from the original on 20 February 2019. Retrieved 19 February 2019.
  109. ^ CIMP-3D. CIMP-3d. Archived from the original on 19 February 2019. Retrieved 18 February 2019.
  110. ^ Momeni, Farhang, Xun Liu, and Jun Ni. "A review of 4D printing". Materials & design 122 (2017): 42-79.
  111. ^ Joshi, Siddharth, et al. "4D printing of materials for the future: Opportunities and challenges." Applied Materials Today 18 (2020): 100490.
  112. ^ "Additive manufacturing – General Principles – Overview of process categories and feedstock". ISO/ASTM International Standard (17296–2:2015(E)). 2015.
  113. ^ "Standard Terminology for Additive Manufacturing – General Principles – Terminology". ASTM International – Standards Worldwide. 1 December 2015. Archived from the original on 9 February 2019. Retrieved 23 August 2019.
  114. ^ Sherman, Lilli Manolis (15 November 2007). "A whole new dimension – Rich homes can afford 3D printers". The Economist. Archived from the original on 27 March 2008. Retrieved 24 January 2008.
  115. ^ Wohlers, Terry. "Factors to Consider When Choosing a 3D Printer (WohlersAssociates.com, Nov/Dec 2005)". Archived from the original on 4 November 2020. Retrieved 6 January 2007.
  116. ^ "Casting aluminium parts directly from 3D printed PLA parts". 3ders.org. 25 September 2012. Retrieved 30 October 2013.[permanent dead link]
  117. ^ "How Selective Heat Sintering Works". THRE3D.com. Archived from the original on 3 February 2014. Retrieved 3 February 2014.
  118. ^ Woern, Aubrey; Byard, Dennis; Oakley, Robert; Fiedler, Matthew; Snabes, Samantha (12 August 2018). "Fused Particle Fabrication 3-D Printing: Recycled Materials' Optimization and Mechanical Properties". Materials. 11 (8): 1413. Bibcode:2018Mate...11.1413W. doi:10.3390/ma11081413. PMC 6120030. PMID 30103532.
  119. ^ "Powder bed fusion - DMLS, SLS, SLM, MJF, EBM". make.3dexperience.3ds.com. Archived from the original on 10 April 2019. Retrieved 10 April 2019.
  120. ^ "Aluminium-powder DMLS-printed part finishes race first". Machine Design. 3 March 2014. Archived from the original on 9 July 2023. Retrieved 13 April 2023.
  121. ^ Hiemenz, Joe. "Rapid prototypes move to metal components (EE Times, 3/9/2007)". Archived from the original on 2 November 2012. Retrieved 31 January 2012.
  122. ^ "Rapid Manufacturing by Electron Beam Melting". SMU.edu. Archived from the original on 20 July 2018. Retrieved 18 July 2017.
  123. ^ "Material extrusion - FDM". make.3dexperience.3ds.com. Archived from the original on 9 February 2019. Retrieved 13 March 2019.
  124. ^ "3DEXPERIENCE Platform". make.3dexperience.3ds.com. Archived from the original on 3 April 2023. Retrieved 3 April 2023.
  125. ^ Doyle, Michael; Agarwal, Kuldeep; Sealy, Winston; Schull, Kevin (2015). "Effect of Layer Thickness and Orientation on Mechanical Behavior of Binder Jet Stainless Steel 420 + Bronze Parts". Elsevier Procedia Manufacturing. 1: 251–262. doi:10.1016/j.promfg.2015.09.016. ISSN 2351-9789. S2CID 138624845.
  126. ^ Cameron Coward (7 April 2015). 3D Printing. DK Publishing. p. 74. ISBN 978-1-61564-745-3.
  127. ^ Johnson, R. Colin. "Cheaper avenue to 65 nm? (EE Times, 3/30/2007)".
  128. ^ "The World's Smallest 3D Printer". TU Wien. 12 September 2011. Archived from the original on 20 September 2011. Retrieved 15 September 2011.
  129. ^ "3D-printing multi-material objects in minutes instead of hours". Kurzweil Accelerating Intelligence. 22 November 2013. Archived from the original on 25 January 2021. Retrieved 26 November 2013.
  130. ^ St. Fleur, Nicholas (17 March 2015). "3-D Printing Just Got 100 Times Faster". The Atlantic. Archived from the original on 19 March 2015. Retrieved 19 March 2015.
  131. ^ Beese, Allison M.; Carroll, Beth E. (2015). "Review of Mechanical Properties of Ti-6Al-4V Made by Laser-Based Additive Manufacturing Using Powder Feedstock". JOM. 68 (3): 724. Bibcode:2016JOM....68c.724B. doi:10.1007/s11837-015-1759-z. S2CID 138250882.
  132. ^ Gibson, Ian; Rosen, David; Stucker, Brent (2015). Additive Manufacturing Technologies (PDF). doi:10.1007/978-1-4939-2113-3. ISBN 978-1-4939-2112-6.
  133. ^ a b Kelly, Brett E.; Bhattacharya, Indrasen; Heidari, Hossein; Shusteff, Maxim; Spadaccini, Christopher M.; Taylor, Hayden K. (31 January 2019). "Volumetric additive manufacturing via tomographic reconstruction". Science. 363 (6431): 1075–1079. Bibcode:2019Sci...363.1075K. doi:10.1126/science.aau7114. ISSN 0036-8075. PMID 30705152. S2CID 72336143.
  134. ^ a b "Star Trek–like replicator creates entire objects in minutes". Science. 31 January 2019. Archived from the original on 19 May 2022. Retrieved 31 January 2019.
  135. ^ a b Kelly, Brett; Bhattacharya, Indrasen; Shusteff, Maxim; Panas, Robert M.; Taylor, Hayden K.; Spadaccini, Christopher M. (16 May 2017). "Computed Axial Lithography (CAL): Toward Single Step 3D Printing of Arbitrary Geometries". arXiv:1705.05893 [cs.GR].
  136. ^ a b "German RepRap introduces L280, first Liquid Additive Manufacturing (LAM) production-ready 3D printer". 3ders.org. Archived from the original on 13 April 2019. Retrieved 13 April 2019.
  137. ^ Davies, Sam (2 November 2018). "German RepRap to present series-ready Liquid Additive Manufacturing system at Formnext". TCT Magazine. Retrieved 13 April 2019.
  138. ^ "German RepRap presenting Liquid Additive Manufacturing technology at RAPID+TCT". TCT Magazine. 10 May 2017. Retrieved 13 April 2019.
  139. ^ Scott, Clare (2 November 2018). "German RepRap to Present Liquid Additive Manufacturing and L280 3D Printer at Formnext". 3DPrint.com | The Voice of 3D Printing / Additive Manufacturing. Archived from the original on 13 April 2019. Retrieved 13 April 2019.
  140. ^ "German RepRap develops new polyurethane material for Liquid Additive Manufacturing". TCT Magazine. 2 August 2017. Retrieved 13 April 2019.
  141. ^ "Essentium to acquire collider to advance DLP 3D printing technology". Make Parts Fast. 20 July 2021. Archived from the original on 3 April 2023. Retrieved 3 April 2023.
  142. ^ "3D Printer Uses Standard Paper". www.rapidtoday.com. Archived from the original on 9 November 2020. Retrieved 19 March 2013.
  143. ^ Yang, Y.; Gong, Y.; Qu, S. (2019). "Additive/subtractive hybrid manufacturing of 316L stainless steel powder: Densification, microhardness and residual stress". J Mech Sci Technol. 33 (12): 5797–5807. doi:10.1007/s12206-019-1126-z. S2CID 214298577.
  144. ^ Boisselier, D.; Sankaré, S.; Engel, T. (2014). "Improvement of the Laser Direct Metal Deposition Process in 5-axis Configuration". Physics Procedia. 56 (8th International Conference on Laser Assisted Net Shape Engineering LANE 2014): 239–249. Bibcode:2014PhPro..56..239B. doi:10.1016/j.phpro.2014.08.168. S2CID 109491084.
  145. ^ Li, L.; Haghighi, A.; Yang, Y. (2018). "A novel 6-axis hybrid additive-subtractive manufacturing process: Design and case studies". Journal of Manufacturing Processes. 33: 150–160. doi:10.1016/j.jmapro.2018.05.008. S2CID 139579311.
  146. ^ "Saving with Feature Additions". BeAM Machines. 17 July 2020. Archived from the original on 4 July 2022. Retrieved 29 April 2022.
  147. ^ Beese, Allison M.; Carroll, Beth E. (21 December 2015). "Review of Mechanical Properties of Ti-6Al-4V Made by Laser-Based Additive Manufacturing Using Powder Feedstock". JOM. 68 (3): 724–734. Bibcode:2016JOM....68c.724B. doi:10.1007/s11837-015-1759-z. ISSN 1047-4838. S2CID 138250882.
  148. ^ Gibson, Ian; Rosen, David; Stucker, Brent (2015). "Chapter 10". Additive Manufacturing Technologies - Springer (PDF). doi:10.1007/978-1-4939-2113-3. ISBN 978-1-4939-2112-6. S2CID 114833020. Archived (PDF) from the original on 29 August 2023. Retrieved 14 August 2023.
  149. ^ Surovi, Nowrin Akter; Hussain, Shaista; Soh, Gim Song (2022). A Study of Machine Learning Framework for Enabling Early Defect Detection in Wire Arc Additive Manufacturing Processes. International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. Vol. 86229. pp. V03AT03A002.
  150. ^ Nilsiam, Yuenyong; Haselhuhn, Amberlee; Wijnen, Bas; Sanders, Paul; Pearce, Joshua M. (2015). "Integrated Voltage – Current Monitoring and Control of Gas Metal Arc Weld Magnetic Ball-Jointed Open Source 3-D Printer". Machines. 3 (4): 339–51. doi:10.3390/machines3040339.
  151. ^ Pinar, A.; Wijnen, B.; Anzalone, G. C.; Havens, T. C.; Sanders, P. G.; Pearce, J. M. (2015). "Low-cost Open-Source Voltage and Current Monitor for Gas Metal Arc Weld 3-D Printing". Journal of Sensors. 2015: 1–8. doi:10.1155/2015/876714.
  152. ^ Magalhães, Samuel; Sardinha, Manuel; Vicente, Carlos; Leite, Marco; Ribeiro, Relógio; Vaz, Maria; Reis, Luís (23 August 2021). "Validation of a low-cost selective powder deposition process through the characterization of tin bronze specimens". The Journal of Materials: Design and Applications. 235 (12): 2681–2691. doi:10.1177/14644207211031941. S2CID 238738655.
  153. ^ Li, Zongan; Xu, Mengjia; Wang, Jiahang; Zhang, Feng (October 2022). "Recent Advances in Cryogenic 3D Printing Technologies". Advanced Engineering Materials. 24 (10): 2200245. doi:10.1002/adem.202200245. ISSN 1438-1656. S2CID 248488161.
  154. ^ a b Zhang, Wei; Leu, Ming C; Ji, Zhiming; Yan, Yongnian (1 June 1999). "Rapid freezing prototyping with water". Materials & Design. 20 (2): 139–145. doi:10.1016/S0261-3069(99)00020-5. ISSN 0261-3069.
  155. ^ Tan, Zhengchu; Parisi, Cristian; Di Silvio, Lucy; Dini, Daniele; Forte, Antonio Elia (24 November 2017). "Cryogenic 3D Printing of Super Soft Hydrogels". Scientific Reports. 7 (1): 16293. Bibcode:2017NatSR...716293T. doi:10.1038/s41598-017-16668-9. ISSN 2045-2322. PMC 5701203. PMID 29176756.
  156. ^ Xiong, Zhuo; Yan, Yongnian; Wang, Shenguo; Zhang, Renji; Zhang, Chao (7 June 2002). "Fabrication of porous scaffolds for bone tissue engineering via low-temperature deposition". Scripta Materialia. 46 (11): 771–776. doi:10.1016/S1359-6462(02)00071-4. ISSN 1359-6462.
  157. ^ Huang, Tieshu; Mason, Michael S.; Hilmas, Gregory E.; Leu, Ming C. (1 June 2006). "Freeze-form extrusion fabrication of ceramic parts". Virtual and Physical Prototyping. 1 (2): 93–100. doi:10.1080/17452750600649609. ISSN 1745-2759. S2CID 135763440.
  158. ^ Taufik, Mohammad; Jain, Prashant K. (10 December 2016). "Additive Manufacturing: Current Scenario". Proceedings of International Conference on: Advanced Production and Industrial Engineering -ICAPIE 2016: 380–386. Archived from the original on 1 October 2020. Retrieved 31 May 2017.
  159. ^ a b Corsini, Lucia; Aranda-Jan, Clara B.; Moultrie, James (2019). "Using digital fabrication tools to provide humanitarian and development aid in low-resource settings". Technology in Society. 58: 101117. doi:10.1016/j.techsoc.2019.02.003. ISSN 0160-791X. Archived from the original on 29 April 2023. Retrieved 23 August 2019.
  160. ^ Vincent (January–February 2011). "Origins: A 3D Vision Spawns Stratasys, Inc". Today's Machining World. Vol. 7, no. 1. pp. 24–25. Archived from the original on 6 October 2023. Retrieved 27 March 2023.
  161. ^ Wong, Venessa (28 January 2014). "A Guide to All the Food That's Fit to 3D Print (So Far)". Bloomberg.com. Archived from the original on 18 July 2019. Retrieved 4 March 2017.
  162. ^ "Did BeeHex Just Hit "Print" to Make Pizza at Home?". 27 May 2016. Archived from the original on 21 February 2023. Retrieved 28 May 2016.
  163. ^ "Foodini 3D Printer Cooks Up Meals Like the Star Trek Food Replicator". Archived from the original on 2 May 2020. Retrieved 27 January 2015.
  164. ^ "3D Printed Food System for Long Duration Space Missions". sbir.gsfc.nasa.gov. Archived from the original on 24 July 2020. Retrieved 24 April 2019.
  165. ^ Bejerano, Pablo G. (28 September 2018). "Barcelona researcher develops 3D printer that makes 'steaks'". El País. ISSN 1134-6582. Archived from the original on 25 December 2019. Retrieved 21 June 2019.
  166. ^ Lidia Montes; Ruqayyah Moynihan. "A researcher has developed a plant-based meat substitute that's made with a 3D printer". Business Insider. Archived from the original on 15 November 2023. Retrieved 21 June 2019.
  167. ^ a b "3D Printed Clothing Becoming a Reality". Resins Online. 17 June 2013. Archived from the original on 1 November 2013. Retrieved 30 October 2013.
  168. ^ Michael Fitzgerald (28 May 2013). "With 3-D Printing, the Shoe Really Fits". MIT Sloan Management Review. Archived from the original on 8 November 2020. Retrieved 30 October 2013.
  169. ^ Sharma, Rakesh (10 September 2013). "3D Custom Eyewear The Next Focal Point For 3D Printing". Forbes.com. Archived from the original on 13 September 2013. Retrieved 10 September 2013.
  170. ^ "3D Printing: Challenges and Opportunities for International Relations". Council on Foreign Relations. 23 October 2013. Archived from the original on 28 October 2013. Retrieved 30 October 2013.
  171. ^ "Koenigsegg One:1 Comes With 3D Printed Parts". Business Insider. Archived from the original on 9 December 2020. Retrieved 14 May 2014.
  172. ^ "Conheça o Urbee, primeiro carro a ser fabricado com uma impressora 3D". tecmundo.com.br. 3 November 2010.
  173. ^ Eternity, Max (23 November 2014). "The Urbee 3D-Printed Car: Coast to Coast on 10 Gallons?".
  174. ^ 3D Printed Car Creator Discusses Future of the Urbee on YouTube
  175. ^ "Local Motors shows Strati, the world's first 3D-printed car". 13 January 2015. Archived from the original on 29 June 2016. Retrieved 21 July 2016.
  176. ^ Simmons, Dan (6 May 2015). "Airbus had 1,000 parts 3D printed to meet deadline". BBC. Archived from the original on 4 November 2020. Retrieved 27 November 2015.
  177. ^ Zitun, Yoav (27 July 2015). "The 3D printer revolution comes to the IAF". Ynetnews. Ynet News. Archived from the original on 29 September 2015. Retrieved 29 September 2015.
  178. ^ Zelinski, Peter (31 March 2017), "GE team secretly printed a helicopter engine, replacing 900 parts with 16", Modern Machine Shop, retrieved 9 April 2017.
  179. ^ Greenberg, Andy (23 August 2012). "'Wiki Weapon Project' Aims To Create A Gun Anyone Can 3D-Print at Home". Forbes. Archived from the original on 25 August 2012. Retrieved 27 August 2012.
  180. ^ Poeter, Damon (24 August 2012). "Could a "Printable Gun" Change the World?". PC Magazine. Archived from the original on 27 August 2012. Retrieved 27 August 2012.
  181. ^ Samsel, Aaron (23 May 2013). "3D Printers, Meet Othermill: A CNC machine for your home office (VIDEO)". Guns.com. Archived from the original on 4 October 2018. Retrieved 30 October 2013.
  182. ^ "The Third Wave, CNC, Stereolithography, and the end of gun control". Popehat. 6 October 2011. Archived from the original on 12 December 2020. Retrieved 30 October 2013.
  183. ^ Rosenwald, Michael S. (25 February 2013). "Weapons made with 3-D printers could test gun-control efforts". Washington Post. Archived from the original on 20 October 2019. Retrieved 23 August 2017.
  184. ^ "Making guns at home: Ready, print, fire". The Economist. 16 February 2013. Archived from the original on 2 November 2013. Retrieved 30 October 2013.
  185. ^ Rayner, Alex (6 May 2013). "3D-printable guns are just the start, says Cody Wilson". The Guardian. London. Archived from the original on 31 July 2013. Retrieved 10 December 2016.
  186. ^ Manjoo, Farhad (8 May 2013). "3-D-printed gun: Yes, it will be possible to make weapons with 3-D printers. No, that doesn't make gun control futile". Slate.com. Archived from the original on 5 December 2018. Retrieved 30 October 2013.
  187. ^ Islam, Muhammed Kamrul; Hazell, Paul J.; Escobedo, Juan P.; Wang, Hongxu (July 2021). "Biomimetic armour design strategies for additive manufacturing: A review". Materials & Design. 205: 109730. doi:10.1016/j.matdes.2021.109730.
  188. ^ Eppley, B. L.; Sadove, A. M. (1 November 1998). "Computer-generated patient models for reconstruction of cranial and facial deformities". J Craniofac Surg. 9 (6): 548–556. doi:10.1097/00001665-199811000-00011. PMID 10029769.
  189. ^ Poukens, Jules (1 February 2008). "A classification of cranial implants based on the degree of difficulty in computer design and manufacture". The International Journal of Medical Robotics and Computer Assisted Surgery. 4 (1): 46–50. doi:10.1002/rcs.171. PMID 18240335. S2CID 26121479.
  190. ^ Perry, Keith (12 March 2014). "Man makes surgical history after having his shattered face rebuilt using 3D printed parts". The Daily Telegraph. London. Archived from the original on 11 January 2022. Retrieved 12 March 2014.
  191. ^ Zopf, David A.; Hollister, Scott J.; Nelson, Marc E.; Ohye, Richard G.; Green, Glenn E. (2013). "Bioresorbable Airway Splint Created with a Three-Dimensional Printer". New England Journal of Medicine. 368 (21): 2043–5. doi:10.1056/NEJMc1206319. PMID 23697530.
  192. ^ Moore, Calen (11 February 2014). "Surgeons have implanted a 3-D-printed pelvis into a U.K. cancer patient". fiercemedicaldevices.com. Archived from the original on 14 June 2016. Retrieved 4 March 2014.
  193. ^ "3D-printed sugar network to help grow artificial liver". BBC News. 2 July 2012. Archived from the original on 13 September 2020. Retrieved 21 July 2018.
  194. ^ "RFA-HD-15-023: Use of 3-D Printers for the Production of Medical Devices (R43/R44)". NIH grants. Archived from the original on 31 March 2023. Retrieved 30 September 2015.
  195. ^ Belgrano, Fabricio dos Santos; Diegel, Olaf; Pereira, Nei; Hatti-Kaul, Rajni (2018). "Cell immobilization on 3D-printed matrices: A model study on propionic acid fermentation". Bioresource Technology. 249: 777–782. Bibcode:2018BiTec.249..777B. doi:10.1016/j.biortech.2017.10.087. PMID 29136932.
  196. ^ Melocchi, Alice; Uboldi, Marco; Cerea, Matteo; Foppoli, Anastasia; Maroni, Alessandra; Moutaharrik, Saliha; Palugan, Luca; Zema, Lucia; Gazzaniga, Andrea (1 October 2020). "A Graphical Review on the Escalation of Fused Deposition Modeling (FDM) 3D Printing in the Pharmaceutical Field". Journal of Pharmaceutical Sciences. 109 (10): 2943–2957. doi:10.1016/j.xphs.2020.07.011. hdl:2434/828138. ISSN 0022-3549. PMID 32679215. S2CID 220630295.
  197. ^ Afsana; Jain, Vineet; Haider, Nafis; Jain, Keerti (20 March 2019). "3D Printing in Personalized Drug Delivery". Current Pharmaceutical Design. 24 (42): 5062–5071. doi:10.2174/1381612825666190215122208. PMID 30767736. S2CID 73421860.
  198. ^ Trenfield, Sarah J; Awad, Atheer; Madla, Christine M; Hatton, Grace B; Firth, Jack; Goyanes, Alvaro; Gaisford, Simon; Basit, Abdul W (3 October 2019). "Shaping the future: recent advances of 3D printing in drug delivery and healthcare" (PDF). Expert Opinion on Drug Delivery. 16 (10): 1081–1094. doi:10.1080/17425247.2019.1660318. ISSN 1742-5247. PMID 31478752. S2CID 201805196. Archived (PDF) from the original on 7 November 2020. Retrieved 5 October 2020.
  199. ^ Schelly, C., Anzalone, G., Wijnen, B., & Pearce, J. M. (2015). "Open-source 3-D printing Technologies for education: Bringing Additive Manufacturing to the Classroom". Journal of Visual Languages & Computing.
  200. ^ Grujović, N., Radović, M., Kanjevac, V., Borota, J., Grujović, G., & Divac, D. (September 2011). "3D printing technology in education environment." In 34th International Conference on Production Engineering (pp. 29–30).
  201. ^ Mercuri, Rebecca; Meredith, Kevin (2014). "An educational venture into 3D Printing". 2014 IEEE Integrated STEM Education Conference. pp. 1–6. doi:10.1109/ISECon.2014.6891037. ISBN 978-1-4799-3229-0. S2CID 16555348.
  202. ^ "Despite Market Woes, 3D Printing Has a Future Thanks to Higher Education – Bold". 2 December 2015. Archived from the original on 30 March 2016. Retrieved 1 April 2016.
  203. ^ Oppliger, Douglas E.; Anzalone, Gerald; Pearce, Joshua M.; Irwin, John L. (15 June 2014). "The RepRap 3-D Printer Revolution in STEM Education". 2014 ASEE Annual Conference & Exposition: 24.1242.1–24.1242.13. ISSN 2153-5868. Archived from the original on 7 July 2023. Retrieved 23 August 2019.
  204. ^ Gillen, Andrew (2016). "Teacher's Toolkit: The New Standard in Technology Education: 3-D Design Class". Science Scope. 039 (9). doi:10.2505/4/ss16_039_09_8. ISSN 0887-2376.
  205. ^ a b Zhang, Chenlong; Anzalone, Nicholas C.; Faria, Rodrigo P.; Pearce, Joshua M. (2013). "Open-Source 3D-Printable Optics Equipment". PLOS ONE. 8 (3): e59840. Bibcode:2013PLoSO...859840Z. doi:10.1371/journal.pone.0059840. PMC 3609802. PMID 23544104.
  206. ^ "UMass Amherst Library Opens 3-D Printing Innovation Center". Library Journal. 2 April 2015. Archived from the original on 2 April 2015. Retrieved 23 August 2019.
  207. ^ Pearce, Joshua M. (14 September 2012). "Building Research Equipment with Free, Open-Source Hardware". Science. 337 (6100): 1303–1304. Bibcode:2012Sci...337.1303P. doi:10.1126/science.1228183. ISSN 0036-8075. PMID 22984059. S2CID 44722829.
  208. ^ Scopigno, R.; Cignoni, P.; Pietroni, N.; Callieri, M.; Dellepiane, M. (2017). "Digital Fabrication Techniques for Cultural Heritage: A Survey]" (PDF). Computer Graphics Forum. 36 (1): 6–21. doi:10.1111/cgf.12781. S2CID 26690232. Archived (PDF) from the original on 12 April 2017. Retrieved 12 April 2017.
  209. ^ "Museum uses 3D printing to take fragile maquette by Thomas Hart Benton on tour through the States". Archived from the original on 17 November 2015.
  210. ^ Vranich, Alexei (December 2018). "Reconstructing ancient architecture at Tiwanaku, Bolivia: the potential and promise of 3D printing". Heritage Science. 6 (1): 65. doi:10.1186/s40494-018-0231-0. S2CID 139309556.
  211. ^ "British Museum releases 3D printer scans of artefacts". Independent.co.uk. 4 November 2014. Archived from the original on 7 November 2014.
  212. ^ "Threeding Uses Artec 3D Scanning Technology to Catalog 3D Models for Bulgaria's National Museum of Military History". 3dprint.com. 20 February 2015. Archived from the original on 17 November 2015. Retrieved 13 November 2015.
  213. ^ Soulellis, P. (2017). Material Speculation: ISIS. In M. Allahyari & D. Rourke (Eds.), The 3D Additivist Cookbook (pp. 129–131). Institute of Network Cultures.
  214. ^ a b Parsinejad, H.; Choi, I.; Yari, M. (2021). "Production of Iranian Architectural Assets for Representation in Museums: Theme of Museum-Based Digital Twin". Body, Space and Technology. 20 (1): 61–74. doi:10.16995/bst.364.
  215. ^ "3D Printed Circuit Boards are the Next Big Thing in Additive Manufacturing". 20 June 2018. Archived from the original on 24 April 2019. Retrieved 24 April 2019.
  216. ^ "Additive Manufacturing Inks & Materials for Custom 3D Printing Solutions". nano-di.com.
  217. ^ Séquin, Carlo H. (2005). "Rapid prototyping". Communications of the ACM. 48 (6): 66–73. doi:10.1145/1064830.1064860. S2CID 2216664. INIST 16817711.
  218. ^ "3D printed clock and gears". Instructables.com. Archived from the original on 26 July 2020. Retrieved 30 October 2013.
  219. ^ "Successful Sumpod 3D printing of a herringbone gear". 3d-printer-kit.com. 23 January 2012. Archived from the original on 2 November 2013. Retrieved 30 October 2013.
  220. ^ ""backscratcher" 3D Models to Print – yeggi". yeggi.com. Archived from the original on 28 November 2020. Retrieved 23 August 2019.
  221. ^ Congressional Research Service. "3D Printing: Overview, Impacts, and the Federal Role" (August 2, 2019) Fas.org
  222. ^ "3D Printing Technology Insight Report, 2014, patent activity involving 3D-Printing from 1990–2013" (PDF). Archived (PDF) from the original on 11 November 2020. Retrieved 10 June 2014.
  223. ^ Thompson, Clive (30 May 2012). "3-D Printing's Legal Morass". Wired. Archived from the original on 21 December 2020. Retrieved 4 March 2017.
  224. ^ a b Weinberg, Michael (January 2013). "What's the Deal with copyright and 3D printing?" (PDF). Institute for Emerging Innovation. Archived from the original (PDF) on 24 November 2020. Retrieved 30 October 2013.
  225. ^ "Homeland Security bulletin warns 3D-printed guns may be "impossible" to stop". Fox News. 23 May 2013. Archived from the original on 24 September 2015. Retrieved 30 October 2013.
  226. ^ "Controlled by Guns". Quiet Babylon. 7 May 2013. Archived from the original on 4 November 2020. Retrieved 30 October 2013.
  227. ^ "3dprinting". Joncamfield.com. Archived from the original on 28 November 2020. Retrieved 30 October 2013.
  228. ^ "State Dept Censors 3D Gun Plans, Citing "National Security"". News.antiwar.com. 10 May 2013. Archived from the original on 7 November 2020. Retrieved 30 October 2013.
  229. ^ "Wishful Thinking Is Control Freaks' Last Defense Against 3D-Printed Guns". Reason.com. 8 May 2013. Archived from the original on 17 January 2019. Retrieved 30 October 2013.
  230. ^ Lennard, Natasha (10 May 2013). "The Pirate Bay steps in to distribute 3-D gun designs". Salon.com. Archived from the original on 11 May 2013. Retrieved 30 October 2013.
  231. ^ "US demands removal of 3D printed gun blueprints". neurope.eu. Archived from the original on 30 October 2013. Retrieved 30 October 2013.
  232. ^ Economía, E. F. E. (9 May 2013). "España y EE.UU. lideran las descargas de los planos de la pistola de impresión casera". El País. ElPais.com. Archived from the original on 27 June 2017. Retrieved 30 October 2013.
  233. ^ "Sen. Leland Yee Proposes Regulating Guns From 3-D Printers". CBS Sacramento. 8 May 2013. Archived from the original on 31 December 2020. Retrieved 30 October 2013.
  234. ^ "Schumer Announces Support For Measure To Make 3D Printed Guns Illegal". 5 May 2013. Archived from the original on 10 December 2020. Retrieved 23 August 2019.
  235. ^ "Four Horsemen of the 3D Printing Apocalypse". Makezine.com. 30 June 2011. Archived from the original on 30 March 2013. Retrieved 30 October 2013.
  236. ^ Ball, James (10 May 2013). "US government attempts to stifle 3D-printer gun designs will ultimately fail". The Guardian. London. Archived from the original on 21 March 2022. Retrieved 10 December 2016.
  237. ^ "Like It Or Not, 3D Printing Will Probably Be Legislated". TechCrunch. 18 January 2013. Archived from the original on 17 November 2013. Retrieved 30 October 2013.
  238. ^ Beckhusen, Robert (15 February 2013). "3-D Printing Pioneer Wants Government to Restrict Gunpowder, Not Printable Guns". Wired. Archived from the original on 11 November 2013. Retrieved 30 October 2013.
  239. ^ Bump, Philip (10 May 2013). "How Defense Distributed Already Upended the World". The Atlantic Wire. Archived from the original on 7 June 2013. Retrieved 30 October 2013.
  240. ^ "News". European Plastics News. Archived from the original on 29 October 2013. Retrieved 30 October 2013.
  241. ^ Cochrane, Peter (21 May 2013). "Peter Cochrane's Blog: Beyond 3D Printed Guns". TechRepublic. Archived from the original on 6 July 2024. Retrieved 30 October 2013.
  242. ^ Gilani, Nadia (6 May 2013). "Gun factory fears as 3D blueprints put online by Defense Distributed". Metro.co.uk. Archived from the original on 8 November 2020. Retrieved 30 October 2013.
  243. ^ "Liberator: First 3D-printed gun sparks gun control controversy". Digitaljournal.com. 6 May 2013. Archived from the original on 4 November 2020. Retrieved 30 October 2013.
  244. ^ "First 3D Printed Gun "The Liberator" Successfully Fired". International Business Times UK. 7 May 2013. Archived from the original on 29 October 2013. Retrieved 30 October 2013.
  245. ^ "FAA prepares guidance for wave of 3D-printed aerospace parts". SpaceNews.com. 20 October 2017. Archived from the original on 6 July 2024. Retrieved 23 August 2019.
  246. ^ "eCFR – Code of Federal Regulations". ecfr.gov. Archived from the original on 4 August 2018. Retrieved 4 August 2018.
  247. ^ "FAA to launch eight-year additive manufacturing road map". 3D Printing Industry. 21 October 2017. Archived from the original on 19 January 2018. Retrieved 18 January 2018.
  248. ^ a b "2017 – Edition 4 – May 5, 2017 – ARSA". arsa.org. Archived from the original on 19 January 2018. Retrieved 18 January 2018.
  249. ^ "Embracing Drones and 3D Printing in the Regulatory Framework". MRO Network. 10 January 2018. Archived from the original on 23 August 2019. Retrieved 23 August 2019.
  250. ^ "3D Printing and monitoring of workers: a new industrial revolution?". osha.europa.eu. 7 June 2017. Archived from the original on 24 September 2017. Retrieved 31 October 2017.
  251. ^ a b c "How Loud Are 3D Printers and Making Them Quiet". 21 July 2020. Archived from the original on 12 November 2022. Retrieved 12 November 2022.
  252. ^ Albert, Mark (17 January 2011). "Subtractive plus additive equals more than (– + + = >)". Modern Machine Shop. Vol. 83, no. 9. p. 14. Archived from the original on 9 December 2020. Retrieved 26 March 2012.
  253. ^ "Jeremy Rifkin and The Third Industrial Revolution Home Page". The third industrial revolution.com. Archived from the original on 25 February 2017. Retrieved 4 January 2016.
  254. ^ "A third industrial revolution". The Economist. 21 April 2012. Archived from the original on 16 June 2018. Retrieved 4 January 2016.
  255. ^ Hollow, Matthew. Confronting a New 'Era of Duplication'? 3D Printing, Replicating Technology and the Search for Authenticity in George O. Smith's Venus Equilateral Series (Thesis). Durham University. Archived from the original on 27 June 2021. Retrieved 21 July 2013.
  256. ^ Ratto, Matt; Ree, Robert (2012). "Materializing information: 3D printing and social change". First Monday. 17 (7). doi:10.5210/fm.v17i7.3968.
  257. ^ "Additive Manufacturing: A supply chain wide response to economic uncertainty and environmental sustainability" (PDF). Archived from the original (PDF) on 15 January 2014. Retrieved 11 January 2014.
  258. ^ a b c d Kostakis, Vasilis (12 January 2013). "At the Turning Point of the Current Techno-Economic Paradigm: Commons-Based Peer Production, Desktop Manufacturing and the Role of Civil Society in the Perezian Framework". TripleC: Communication, Capitalism & Critique. 11 (1): 173–190. doi:10.31269/triplec.v11i1.463. ISSN 1726-670X. Archived from the original on 23 August 2019. Retrieved 23 August 2019.
  259. ^ Kostakis, Vasilis; Papachristou, Marios (2014). "Commons-based peer production and digital fabrication: The case of a Rep Rap-based, Lego-built 3D printing-milling machine". Telematics and Informatics. 31 (3): 434–43. doi:10.1016/j.tele.2013.09.006. S2CID 2297267.
  260. ^ Kostakis, Vasilis; Fountouklis, Michail; Drechsler, Wolfgang (2013). "Peer Production and Desktop Manufacturing". Science, Technology, & Human Values. 38 (6): 773–800. doi:10.1177/0162243913493676. JSTOR 43671156. S2CID 43962759.
  261. ^ Thomas Campbell; Christopher Williams; Olga Ivanova; Banning Garrett (17 October 2011). "Could 3D Printing Change the World?". Atlantic Council. Archived from the original on 23 August 2019. Retrieved 23 August 2019.
  262. ^ Haufe, Patrick; Bowyer, Adrian; Bradshaw, Simon (2010). "The intellectual property implications of low-cost 3D printing". SCRIPTed. 7 (1): 5–31. ISSN 1744-2567.
  263. ^ Gershenfeld, Neil (2008). Fab: The Coming Revolution on Your Desktop—from Personal Computers to Personal Fabrication. Basic Books. pp. 13–14. ISBN 978-0-7867-2204-4. Archived from the original on 6 July 2024. Retrieved 23 August 2019.
  264. ^ "The Inequality Puzzle". Democracy Journal. 14 May 2014. Archived from the original on 23 August 2019. Retrieved 23 August 2019.
  265. ^ a b Spence, Michael (22 May 2014). "Labor's Digital Displacement | by Michael Spence". Project Syndicate. Archived from the original on 8 March 2022. Retrieved 23 August 2019.
  266. ^ Andre, Helene (29 November 2017). "Naomi Wu – "My visibility allows me to direct more attention to important issues and other deserving women"". Women in 3D Printing. Archived from the original on 4 December 2017. Retrieved 3 December 2017.
  267. ^ Lyons Hardcastle, Jessica (24 November 2015). "Is 3D Printing the Future of Sustainable Manufacturing?". Environmental Leader. Archived from the original on 22 January 2019. Retrieved 21 January 2019.
  268. ^ Simpson, Timothy W. (31 January 2018). "Lightweighting with Lattices". Additive Manufacturing. Archived from the original on 22 January 2019. Retrieved 21 January 2019.
  269. ^ Reeves, P. (2012). "Example of Econolyst Research-Understanding the Benefits of AM on CO2" (PDF). The Econolyst. Archived (PDF) from the original on 19 August 2019. Retrieved 21 January 2019.
  270. ^ Gelber, Malte; Uiterkamp, Anton J.M. Schoot; Visser, Cindy (October 2015). "A Global Sustainability Perspective of 3D Printing Technologies". Energy Policy. 74 (1): 158–167. doi:10.1016/j.enpol.2014.08.033.
  271. ^ Peng, Tao; Kellens, Karel; Tang, Renzhong; Chen, Chao; Chen, Gang (May 2018). "Sustainability of additive manufacturing: An overview on its energy demand and environmental impact". Additive Manufacturing. 21 (1): 694–704. doi:10.1016/j.addma.2018.04.022.

Further reading