3D printing.pdf

5/19/2014 3D printing - Wikipedia, the free encyclopedia

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An ORDbot Quantum 3D printer.

Timelapse video of a hyperboloid

object (designed by George W. Hart)

made of PLA using a RepRap "Prusa

Mendel" 3D printer for molten

polymer deposition.

3D printingFrom Wikipedia, the free encyclopedia

For methods of applying a 2D image on a 3D surface, see pad printing. For methods of printing 2D

parallax stereograms that seem 3D to the eye, see lenticular printing and holography.

3D printing or additive manufacturing (AM)[1] is a process ofmaking a three-dimensional solid object of virtually any shape from adigital model. 3D printing is achieved using an additive process,where successive layers of material are laid down in different

shapes.[2] 3D printing is also considered distinct from traditionalmachining techniques, which mostly rely on the removal of material bymethods such as cutting or drilling (subtractive processes).

A 3D printer is a limited type of industrial robot that is capable ofcarrying out an additive process under computer control (such ascomputer numerical control).

The first working 3D printer was created in 1984 by Chuck Hull of

3D Systems Corp.[3] The 3D printing technology was applied first toprototyping (starting in the 1980s), creating rapid prototyping. Itsexpansion into production (job production, mass production, anddistributed manufacturing) was foreseen at that time and took severaldecades to develop. Production roles achieved significant scale forthe first time in the early 2010s. Since the start of the 21st centurythere has been a large growth in the sales of AM machines, and their

price has dropped substantially.[4] According to Wohlers Associates,a consultancy, the market for 3D printers and services was worth

$2.2 billion worldwide in 2012, up 29% from 2011.[5] Applicationsare many, including architecture, construction (AEC), industrialdesign, automotive, aerospace, military, engineering, dental andmedical industries, biotech (human tissue replacement), fashion,footwear, jewelery, eyewear, education, geographic information systems, food, and many other fields.

In industry, machine tool builders have developed machines that include both subtractive and additive

manufacturing in one work envelope,[6] and retrofits of existing machines are underway.[7] In distributed

manufacturing, one study has found[8] that open source 3D printing could become a mass market item becausedomestic 3D printers can offset their capital costs by enabling consumers to avoid costs associated with

purchasing common household objects.[9]

Contents

1 Terminology

2 General principles

2.1 3D printable models

2.2 Printing



2.3 Finishing

3 Additive processes

3.1 Extrusion deposition

3.2 Granular materials binding

3.3 Lamination

3.4 Photopolymerization

3.5 Mask-image-projection-based stereolithography

4 Printers

4.1 Industry use

4.2 Consumer use

5 Applications

5.1 Industrial uses

5.1.1 Rapid prototyping

5.1.2 Rapid manufacturing

5.1.3 Mass customisation

5.1.4 Mass production

5.2 Domestic and hobbyist use

5.3 Clothing

5.4 3D bio-printing

5.5 3D printing for implant and medical device

5.6 3D printing services

5.7 Research into new applications

5.8 Education

6 Intellectual property

7 Effects of 3D printing

7.1 Space exploration

7.2 Social change

7.3 Firearms

7.4 Automotive use

7.5 Materials innovations

8 See also

9 References

10 Bibliography

11 Further reading

12 External links

Terminology



3D model slicing.

The term additive manufacturing refers to technologies that create objects through sequential layering.Objects that are manufactured additively can be used anywhere throughout the product life cycle, from pre-production (i.e., rapid prototyping) to full-scale production (i.e., rapid manufacturing), in addition to tooling

applications and post-production customisation.[10]

In manufacturing, and machining in particular, subtractive methods refers to more traditional methods. The termsubtractive manufacturing is a retronym developed in recent years to distinguish it from newer additivemanufacturing techniques. Although fabrication has included methods that are essentially "additive" for centuries(such as joining plates, sheets, forgings, and rolled work via riveting, screwing, forge welding, or newer kinds ofwelding), it did not include the information technology component of model-based definition. Machining(generating exact shapes with high precision) has typically been subtractive, from filing and turning to milling,

drilling and grinding.[10]

The term stereolithography was defined by Charles W. Hull as a "system for generating three-dimensional

objects by creating a cross-sectional pattern of the object to be formed"in a 1984 patent.[11][12]

General principles

3D printable models

3D printable models may be created with a computer aided designpackage or via 3D scanner. The manual modelling process ofpreparing geometric data for 3D computer graphics is similar toplastic arts such as sculpting. 3D scanning is a process of analysingand collecting digital data on the shape and appearance of a realobject. Based on this data, three-dimensional models of the scannedobject can then be produced.

Both manual and automatic creation of 3D printable models is difficultfor average consumers. This is why several 3D printing marketplaceshave emerged over the last years. Among the most popular are

Shapeways, Thingiverse, MyMiniFactory and Threeding [13][14][15]

Printing

To perform a print, the machine reads the design from 3D printable file (STL file) and lays down successivelayers of liquid, powder, paper or sheet material to build the model from a series of cross sections. These layers,which correspond to the virtual cross sections from the CAD model, are joined or automatically fused to createthe final shape. The primary advantage of this technique is its ability to create almost any shape or geometricfeature.

Printer resolution describes layer thickness and X-Y resolution in dpi (dots per inch), or micrometres. Typicallayer thickness is around 100 m (250 DPI), although some machines such as the Objet Connex series and 3D

Systems' ProJet series can print layers as thin as 16 m (1,600 DPI).[16] X-Y resolution is comparable to thatof laser printers. The particles (3D dots) are around 50 to 100 m (510 to 250 DPI) in diameter.

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 reducethis time to a few hours, although it varies widely depending on the type of machine used and the size andnumber of models being produced simultaneously.



Rapid prototyping worldwide

2001[17]

The Audi RSQ was made with rapid

prototyping industrial KUKA robots.

Traditional techniques like injection moulding can be less expensive for manufacturing polymer products in highquantities, but additive manufacturing can be faster, more flexible and less expensive when producing relativelysmall quantities of parts. 3D printers give designers and concept development teams the ability to produce partsand concept models using a desktop size printer.

Finishing

Though the printer-produced resolution is sufficient for many applications, printing a slightly oversized version ofthe desired object in standard resolution and then removing material with a higher-resolution subtractive processcan achieve greater precision. As with the LUMEX Avance-25 [1](http://www.matsuura.co.jp/english/contents/products/lumex.html) and other machines slated for IMTS 2014IMTS Press Release | International Manufacturing Technology Show(http://www.imts.com/media/imts_releases/20131004.html)

Some additive manufacturing techniques are capable of using multiple materials in the course of constructingparts. Some are able to print in multiple colours and color combinations simultaneously. Some also utilisesupports when building. Supports are removable or dissolvable upon completion of the print, and are used tosupport overhanging features during construction.

Additive processes

Several different 3D printing processes have been invented since thelate 1970s. The printers were originally large, expensive, and highly

limited in what they could produce.[18]

A large number of additive processes are now available. They differ inthe way layers are deposited to create parts and in the materials thatcan be used. Some methods melt or soften material to produce thelayers, e.g. selective laser melting (SLM) or direct metal laser sintering(DMLS), selective laser sintering (SLS), fused deposition modelling(FDM), while others cure liquid materials using different sophisticatedtechnologies, e.g. stereolithography (SLA). With laminated objectmanufacturing (LOM), thin layers are cut to shape and joined together(e.g. paper, polymer, metal). Each method has its own advantagesand drawbacks, and some companies consequently offer a choicebetween powder and polymer for the material from which the object

is built.[19] Some companies use standard, off-the-shelf businesspaper as the build material to produce a durable prototype. The mainconsiderations in choosing a machine are generally speed, cost of the3D printer, cost of the printed prototype, and cost and choice of

materials and color capabilities.[20]

Printers that work directly with metals are expensive. In some cases, however, less expensive printers can be

used to make a mould, which is then used to make metal parts.[21]



Type Technologies Materials

ExtrusionFused depositionmodelling (FDM)

Thermoplastics (e.g. PLA, ABS), HDPE, eutectic metals, edible materials,

Rubber (Sugru), Modelling clay, Plasticine, RTV silicone, Porcelain, Metalclay (including Precious Metal Clay)

Wire

Electron Beam

Freeform

Fabrication

(EBF3)

Almost any metal alloy

Granular

Direct metal laser

sintering (DMLS)Almost any metal alloy

Electron-beam

melting (EBM)Titanium alloys

Selective laser

melting (SLM)Titanium alloys, Cobalt Chrome alloys, Stainless Steel, Aluminium

Selective heatsintering (SHS)[22]

Thermoplastic powder

Selective lasersintering (SLS)

Thermoplastics, metal powders, ceramic powders

Powder bedand inkjet head

3D printing

Plaster-based 3D

printing (PP)Plaster

Laminated

Laminated object

manufacturing

(LOM)

Paper, metal foil, plastic film

Light

polymerised

Stereolithography(SLA)

photopolymer

Digital LightProcessing

(DLP)

photopolymer

Extrusion deposition

Main article: Fused deposition modeling

Fused deposition modelling (FDM) was developed by S. Scott Crump in the late 1980s and was

commercialised in 1990 by Stratasys.[23] With the expiration of the patent on this technology there is now alarge open-source development community, as well as commercial and DIY variants, which utilise this type of3D printer. This has led to a two orders of magnitude price drop since this technology's creation.

In fused deposition modelling the model or part is produced by extruding small beads of material which hardenimmediately to form layers. A thermoplastic filament or metal wire that is wound on a coil is unreeled to supplymaterial to an extrusion nozzle head. The nozzle head heats the material and turns the flow on and off. Typicallystepper motors or servo motors are employed to move the extrusion head and adjust the flow and the head can



Fused deposition modelling: 1

nozzle ejecting molten plastic, 2

deposited material (modeled part), 3

controlled movable table.

The CandyFab granular printing

system uses heated air and granulated

sugar to produce food-grade art

objects.

be moved in both horizontal and vertical directions. Control of thismechanism is typically done by a computer-aided manufacturing(CAM) software package running on a microcontroller.

Various polymers are used, including acrylonitrile butadiene styrene(ABS), polycarbonate (PC), polylactic acid (PLA), high densitypolyethylene (HDPE), PC/ABS, and polyphenylsulfone (PPSU). Ingeneral the polymer is in the form of a filament, fabricated from virginresins. Multiple projects in the open-source community exist that areaimed at processing post-consumer plastic waste into filament. Theseinvolve machines to shred and extrude the plastic material intofilament.

FDM has some restrictions on the shapes that may be fabricated. Forexample, FDM usually cannot produce stalactite-like structures, sincethey would be unsupported during the build. These have to be avoided or a thin support may be designed intothe structure which can be broken away during finishing.

Granular materials binding

Another 3D printing approach is the selective fusing of materials in agranular bed. The technique fuses parts of the layer, and then movesthe working area downwards, adding another layer of granules andrepeating the process until the piece has built up. This process usesthe unfused media to support overhangs and thin walls in the partbeing produced, which reduces the need for temporary auxiliarysupports for the piece. A laser is typically used to sinter the media intoa solid. Examples include selective laser sintering (SLS), with bothmetals and polymers (e.g. PA, PA-GF, Rigid GF, PEEK, PS,Alumide, Carbonmide, elastomers), and direct metal laser sintering(DMLS).

Selective Laser Sintering (SLS) was developed and patented by Dr.Carl Deckard and Dr. Joseph Beaman at the University of Texas at

Austin in the mid-1980s, under sponsorship of DARPA.[24] A similar

process was patented without being commercialised by R. F. Housholder in 1979.[25]

Selective Laser Melting (SLM) does not use sintering for the fusion of powder granules but will completely meltthe powder using a high-energy laser to create fully dense materials in a layerwise method with similarmechanical properties to conventional manufactured metals.

Electron beam melting (EBM) is a similar type of additive manufacturing technology for metal parts (e.g. titaniumalloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a highvacuum. Unlike metal sintering techniques that operate below melting point, EBM parts are fully dense, void-

free, and very strong.[26][27]

Another method consists of an inkjet 3D printing system. The printer creates the model one layer at a time byspreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using aninkjet-like process. This is repeated until every layer has been printed. This technology allows the printing of fullcolor prototypes, overhangs, and elastomer parts. The strength of bonded powder prints can be enhanced withwax or thermoset polymer impregnation.



Stereolithography apparatus.

Lamination

Main article: Laminated object manufacturing

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

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

prototype.[28]

There are also a number of companies selling printers that print laminated objects using thin plastic and metalsheets.

Photopolymerization

Main article: Stereolithography

Stereolithography was patented in 1986 by Chuck Hull.[29]

Photopolymerization is primarily used in stereolithography (SLA) toproduce a solid part from a liquid. This process dramatically redefinedprevious efforts, from the Photosculpture method of Franois Willme

(18301905) in 1860[30] through the photopolymerisation of

Mitsubishi` s Matsubara in 1974.[31]

In photopolymerisation, a vat of liquid polymer is exposed tocontrolled lighting under safelight conditions. The exposed liquidpolymer hardens. The build plate then moves down in smallincrements and the liquid polymer is again exposed to light. Theprocess repeats until the model has been built. The liquid polymer is then drained from the vat, leaving the solid

model. The EnvisionTEC Perfactory[32] is an example of a DLP rapid prototyping system.

Inkjet printer systems like the Objet PolyJet system spray photopolymer materials onto a build tray in ultra-thinlayers (between 16 and 30 m) until the part is completed. Each photopolymer layer is cured with UV light afterit is jetted, producing fully cured models that can be handled and used immediately, without post-curing. Thegel-like support material, which is designed to support complicated geometries, is removed by hand and waterjetting. It is also suitable for elastomers.

Ultra-small features can be made with the 3D microfabrication technique used in multiphotonphotopolymerisation. This approach traces the desired 3D object in a block of gel using a focused laser. Due tothe nonlinear nature of photoexcitation, the gel is cured to a solid only in the places where the laser was focusedand 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.[33]

Yet another approach uses a synthetic resin that is solidified using LEDs.[34]

Mask-image-projection-based stereolithography



RepRap version 2.0 (Mendel).

In this technique 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.[35]

In research systems, the light is projected from below, allowing the resin to be quickly spread into uniform thin

layers, reducing production time from hours to minutes.[35]

The technique has been used to create objects composed of multiple materials that cure at different rates.[35]

Commercially available devices such as Objet Connex apply the resin via small nozzles.[35]

Printers

Industry use

As of October 2012, Stratasys, the result of a merger of an American and an Israeli company, now sellsadditive manufacturing systems that range from $2,000 to $500,000; General Electric uses the high-end model

to build parts for turbines.[36]

Consumer use

Several projects and companies are making efforts to developaffordable 3D printers for home desktop use. Much of this work hasbeen driven by and targeted at DIY/enthusiast/early adoptercommunities, with additional ties to the academic and hacker

communities.[37]

RepRap is one of the longest running projects in the desktopcategory. The RepRap project aims to produce a free and open

source hardware (FOSH)[38] 3D printer, whose full specifications arereleased under the GNU General Public License, and which iscapable of replicating itself by printing many of its own (plastic) parts

to create more machines.[39][40] RepRaps have already been shown

to be able to print circuit boards[41] and metal parts.[42][43]

Because of the FOSH aims of RepRap, many related projects have used their design for inspiration, creating anecosystem of related or derivative 3D printers, most of which are also open source designs. The availability ofthese open source designs means that variants of 3D printers are easy to invent. The quality and complexity ofprinter designs, however, as well as the quality of kit or finished products, varies greatly from project to project.This rapid development of open source 3D printers is gaining interest in many spheres as it enables hyper-customization and the use of public domain designs to fabricate open source appropriate technology throughconduits such as Thingiverse and Cubify. This technology can also assist initiatives in sustainable development

since technologies are easily and economically made from resources available to local communities.[44][45]

The cost of 3D printers has decreased dramatically since about 2010, with machines that used to cost $20,000

now costing less than $1,000.[46] For instance, as of 2013, several companies and individuals are selling parts to

build various RepRap designs, with prices starting at about 400 / US$500.[47] The open source Fab@Home

project[48] has developed printers for general use with anything that can be squirted through a nozzle, from



MakerBot Cupcake CNC.

Printing in progress in a Ultimaker 3D

printer during Mozilla Maker party,

Bangalore

chocolate to silicone sealant and chemical reactants. Printers following the project's designs have been available

from suppliers in kits or in pre-assembled form since 2012 at prices in the US$2000 range.[47] The Kickstarter

funded Peachy Printer is designed to cost $100[49] and several other new 3D printers are aimed at the small,inexpensive market including the mUVe3D and Lumifold. Rapide 3D has designed a professional grade

crowdsourced 3D-printer costing $1499 which has no fumes nor constant rattle during use.[50] The 3Doodler,

"3D printing pen", raised $2.3 million on Kickstarter with the pens selling at $99,[51] though the 3D Doodler has

been criticised for being more of a crafting pen than a 3D printer.[52]

As the costs of 3D printers have come down they are becoming more appealing financially to use for self-

manufacturing of personal products.[9] In addition, 3D printing products at home may reduce the environmental

impacts of manufacturing by reducing material use and distribution impacts.[53]

In addition, several RecycleBots such as the commercialised Filastrucer have been designed and fabricated to

convert waste plastic, such as shampoo containers and milk jugs, into inexpensive RepRap filament.[54] There issome evidence that using this approach of distributed recycling is

better for the environment.[55]

The development and hyper-customization of the RepRap-based 3Dprinters has produced a new category of printers suitable for small

business and consumer use. Manufacturers such as Solidoodle,[36]

RoBo, and RepRapPro have introduced models and kits priced atless than $1,000, thousands less than they were in September

2012.[36] Depending on the application, the print resolution and speedof manufacturing lies somewhere between a personal printer and anindustrial printer. A list of printers with pricing and other information is

maintained.[47] Most recently delta robots, like the TripodMaker,have been utilised for 3D printing to increase fabrication speed

further.[56] For delta 3D printers, due to its geometry anddifferentiation movements, the accuracy of the print depends on the

position of the printer head.[57]

Some companies are also offering software for 3D printing, as a

support for hardware manufactured by other companies.[58]

Applications



Airwolf 3D AW3D v.4 (Prusa).

An example of 3D printed limited

edition jewellery. This necklace is

made of glassfiber-filled dyed nylon.

It has rotating linkages that were

produced in the same manufacturing

step as the other parts.

Three-dimensional printing makes it as cheap to create single items as it is to producethousands and thus undermines economies of scale. It may have as profound an impact on theworld as the coming of the factory did....Just as nobody could have predicted the impact ofthe steam engine in 1750or the printing press in 1450, or the transistor in 1950it isimpossible to foresee the long-term impact of 3D printing. But the technology is coming, and itis likely to disrupt every field it touches.

The Economist, in a February 10, 2011 leader[59]

Additive manufacturing's earliest applications have been on thetoolroom end of the manufacturing spectrum. For example, rapidprototyping was one of the earliest additive variants, and its missionwas to reduce the lead time and cost of developing prototypes of newparts and devices, which was earlier only done with subtractive

toolroom methods (typically slowly and expensively).[60] Withtechnological advances in additive manufacturing, however, and thedissemination of those advances into the business world, additivemethods are moving ever further into the production end of

manufacturing in creative and sometimes unexpected ways.[60] Partsthat were formerly the sole province of subtractive methods can nowin some cases be made more profitably via additive ones.

Standard applications include design visualisation, prototyping/CAD,metal casting, architecture, education, geospatial, healthcare, andentertainment/retail.

Industrial uses

Rapid prototyping

Main article: rapid prototyping



Guardians of Time by Manfred

Kielnhofer, 3D printing polished

nickel steel by Shapeways 2014

Full color miniature face models

produced on a 3D Printer.

Industrial 3D printers have existed since the early 1980s and have been used extensively for rapid prototypingand research purposes. These are generally larger machines that use proprietary powdered metals, castingmedia (e.g. sand), plastics, paper or cartridges, and are used for rapid prototyping by universities andcommercial companies.

Rapid manufacturing

Advances in RP technology have introduced materials that areappropriate for final manufacture, which has in turn introduced thepossibility of directly manufacturing finished components. Oneadvantage of 3D printing for rapid manufacturing lies in the relativelyinexpensive production of small numbers of parts.

Rapid manufacturing is a new method of manufacturing and many ofits processes remain unproven. 3D printing is now entering the field ofrapid manufacturing and was identified as a "next level" technology by

many experts in a 2009 report.[61] One of the most promisingprocesses looks to be the adaptation of selective laser sintering(SLS), or direct metal laser sintering (DMLS) some of the better-established rapid prototyping methods. As of 2006, however, thesetechniques were still very much in their infancy, with many obstaclesto be overcome before RM could be considered a realistic

manufacturing method.[62]

Mass customisation

Companies have created services where consumers can customiseobjects using simplified web based customisation software, and order

the resulting items as 3D printed unique objects.[63][64] This now

allows consumers to create custom cases for their mobile phones.[65]

Nokia has released the 3D designs for its case so that owners can

customise their own case and have it 3D printed.[66]

Mass production

The current slow print speed of 3D printers limits their use for massproduction. To reduce this overhead, several fused filament machinesnow offer multiple extruder heads. These can be used to print inmultiple colours, with different polymers, or to make multiple printssimultaneously. This increases their overall print speed during multipleinstance production, while requiring less capital cost than duplicatemachines since they can share a single controller.

Distinct from the use of multiple machines, multi-material machines are restricted to making identical copies ofthe same part, but can offer multi-color and multi-material features when needed. The print speed increasesproportionately to the number of heads. Furthermore, the energy cost is reduced due to the fact that they sharethe same heated print volume. Together, these two features reduce overhead costs.



Printing going on with a 3D printer at

Makers Party Bangalore 2013,

Bangalore

CartesioLDMP mass production

3Dprinter

A MakerBot Replicator 2

Many printers now offer twin print heads. However, these are used to manufacture single (sets of) parts inmultiple colours/materials.

Few studies have yet been done in this field to see if conventional subtractive methods are comparable toadditive methods.

Domestic andhobbyist use

As of 2012, domestic 3Dprinting has mainlycaptivated hobbyists andenthusiasts and has notquite gained recognition forpractical householdapplications. A working

clock has been made[67]

and gears have been printed for home woodworking machines[68]

among other purposes.[69] 3D printing is also used for ornamentalobjects. Web sites associated with home 3D printing tend to includebackscratchers, coathooks, doorknobs etc.

As of 2013, 3D printers have been used to help animals. A 3D

printed foot let a crippled duckling walk again.[70] 3D printed stylish

hermit crab shells let them inhabit a new style home.[71] Printers havealso made decorative pieces for humans such as necklaces, rings,bags etc.

As of 2014, 3D printers have been used to help children receive cost effective prosthetic, in home use as well asin developing countries. In addition, 3D printing also created a skull implant for a adult human patient that wasaccepted by the patient. In addition, 3D printing has been used to produce fashion garments, as well asfootwear.

The open source Fab@Home project[48] has developed printers for general use. They have been used inresearch environments to produce chemical compounds with 3D printing technology, including new ones, initially

without immediate application as proof of principle.[72] The printer can print with anything that can be dispensedfrom a syringe as liquid or paste. The developers of the chemical application envisage that this technology couldbe used for both industrial and domestic use. Including, for example, enabling users in remote locations to be

able to produce their own medicine or household chemicals.[73][74]

The OpenReflex analogue SLR camera was developed for 3D printing as an open source student project.[75]

Clothing

3D printing has spread into the world of clothing with fashion designers experimenting with 3D-printed bikinis,

shoes, and dresses.[76] In commercial production Nike is using 3D printing to prototype and manufacture the2012 Vapor Laser Talon football shoe for players of American football, and New Balance is 3D manufacturing

custom-fit shoes for athletes.[76][77]



3D bio-printing

As of 2012, 3D bio-printing technology has been studied by biotechnology firms and academia for possible usein tissue engineering applications in which organs and body parts are built using inkjet techniques. In thisprocess, 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.[78] The first production system for 3D tissue printing was

delivered in 2009, based on NovoGen bioprinting technology.[79] Several terms have been used to refer to this

field of research: organ printing, bio-printing, body part printing,[80] and computer-aided tissue engineering,

among others.[81]

An early-stage medical laboratory and research company, called Organovo, designs and develops functional,three dimensional human tissue for medical research and therapeutic applications. The company utilises itsNovoGen MMX Bioprinter for 3D bioprinting. Organovo anticipates that the bioprinting of human tissues willaccelerate the preclinical drug testing and discovery process, enabling treatments to be created more quicklyand at lower cost. Additionally, Organovo has long-term expectations that this technology could be suitable for

surgical therapy and transplantation.[82]

In 2014, researchers successfully implanted a 3D printed skull component into a patient, without any adverseaffects. This new finding gives the opportunity for new implants to be custom tailored to the patient, in manydifferent applications. This allows for new greater innovation when it comes to 3D printed implants.

3D printing for implant and medical device

3D printing has been used to print patient specific implant and device for medical use. Successful operationsinclude a titanium pelvic implanted into a British patient, titanium lower jaw transplanted to a Dutch patient, and

a plastic tracheal splint for an American infant.[83] The hearing aid and dental industries are expected to be the

biggest area of future development using the custom 3D printing technology.[84] In March 2014, surgeons inSwansea used 3D printed parts to rebuild the face of a motorcyclist who had been seriously injured in a road

accident.[85]

3D printing services

Some companies offer on-line 3D printing services open to both consumers and industries.[86] Such servicesrequire people to upload their 3D designs to the company website. Designs are then 3D printed using industrial3D printers and either shipped to the customer or in some cases, the consumer can pick the object up at the

store.[87] This allows for increased social interactions between members of the 3D printing community.

Research into new applications

Future applications for 3D printing might include creating open-source scientific equipment to create open

source labs [89][90] or other science-based applications like reconstructing fossils in palaeontology, replicatingancient and priceless artefacts in archaeology, reconstructing bones and body parts in forensic pathology, andreconstructing heavily damaged evidence acquired from crime scene investigations. The technology is also

currently being researched for building construction.[91][92][93][94][95]



VLT component created using 3D

printing.[88]

In 2005, academic journals had begun to report on the possible artistic applications of 3D printing

technology.[96] By 2007 the mass media followed with an article in the Wall Street Journal[97] and Time

Magazine, listing a 3D printed design among their 100 most influential designs of the year.[98] During the 2011London Design Festival, an installation, curated by Murray Moss and focused on 3D Printing, was held in theVictoria and Albert Museum (the V&A). The installation was called Industrial Revolution 2.0: How the

Material World will Newly Materialize.[99]

A proof-of-principle project at the University of Glasgow, UK, in 2012 showed that it is possible to use 3Dprinting techniques to create chemical compounds, including newones. They first printed chemical reaction vessels, then used theprinter to squirt reactants into them as "chemical inks" which would

then react.[72] They have produced new compounds to verify thevalidity of the process, but have not pursued anything with a particular

application.[72] Cornell Creative Machines Lab has confirmed that it ispossible to produce customised food with 3D Hydrocolloid

Printing.[100] Professor Leroy Cronin of Glasgow Universityproposed, in a TED Talk that it should one day be possible to use

chemical inks to print medicine.[101] 3D food printer is currently beingdevelop by squeezing out food, layer by layer, for food such as

chocolate, candy, and pasta.[102]

The use of 3D scanning technologies allows the replication of realobjects without the use of moulding techniques that in many cases can be more expensive, more difficult, or too

invasive to be performed, particularly for precious or delicate cultural heritage artefacts[103] where direct contactwith the moulding substances could harm the original object's surface.

An additional use being developed is building printing, or using 3D printing to build buildings. This could allow

faster construction for lower costs, and has been investigated for construction of off-Earth habitats.[91][104] Forexample, the Sinterhab project is researching a lunar base constructed by 3D printing using lunar regolith as abase material. Instead of adding a binding agent to the regolith, researchers are experimenting with microwave

sintering to create solid blocks from the raw material.[105]

Employing additive layer technology offered by 3D printing, Terahertz devices which act as waveguides,couplers and bends have been created. The complex shape of these devices could not be achieved usingconventional fabrication techniques. Commercially available professional grade printer EDEN 260V was used tocreate structures with minimum feature size of 100 m. The printed structures were later DC sputter coated with

gold (or any other metal) to create a Terahertz Plasmonic Device. [106]

China has committed almost $500 million towards the establishment of 10 national 3-D printing development

institutes.[107] In 2013, Chinese scientists began printing ears, livers and kidneys, with living tissue. Researchersin China have been able to successfully print human organs using specialised 3D bio printers that use living cellsinstead of plastic. Researchers at Hangzhou Dianzi University actually went as far as inventing their own 3Dprinter for the complex task, dubbed the Regenovo which is a "3D bio printer." Xu Mingen, Regenovo'sdeveloper, said that it takes the printer under an hour to produce either a mini liver sample or a four to five inchear cartilage sample. Xu also predicted that fully functional printed organs may be possible within the next ten to

twenty years.[108][109] In the same year, researchers at the University of Hasselt, in Belgium had successfullyprinted a new jawbone for an 83-year-old Belgian woman. The woman is now able to chew, speak and breathe

normally again after a machine printed her a new jawbone.[110]



In Bahrain, large-scale 3D printing using a sandstone-like material has been used to create unique coral-shapedstructures, which encourage coral polyps to colonise and regenerate damaged reefs. These structures have amuch more natural shape than other structures used to create artificial reefs, and have a neutral pH which

concrete does not.[111]

Some of the recent developments in 3D printing were revealed at the 3DPrintshow in London, which took placein November 2013 and 2014. The art section had in exposition artworks made with 3D printed plastic andmetal. Several artists such as Joshua Harker, Davide Prete, Sophie Kahn, Helena Lukasova, Foteini Setakishowed how 3D printing can modify aesthetic and art processes. One part of the show focused on ways inwhich 3D printing can advance the medical field. The underlying theme of these advances was that these printerscan be used to create parts that are printed with specifications to meet each individual. This makes the processsafer and more efficient. One of these advances is the use of 3D printers to produce casts that are created tomimic the bones that they are supporting. These custom-fitted casts are open, which allow the wearer to scratchany itches and also wash the damaged area. Being open also allows for open ventilation. One of the best

features is that they can be recycled to create more casts.[112] In December 2013, BAE Systems fitted and

successfully test flew a Panavia Tornado with parts made by 3D printing.[113]

Education

3D printing is the latest technology making inroads into the classroom 3D printing allows students to createprototypes of items without the use of expensive tooling required in subtractive methods. Students design andproduce actual models they can hold. The classroom environment allows students to learn and employ new

applications for 3D printing.[114]

Students discover the capabilities with 3D printing. Engineering and design principles are explored as well asarchitectural planning. Students recreate duplicates of museum items such as fossils and historical artefacts forstudy in the classroom without possibly damaging sensitive collections. Other students interested in graphicdesigning can construct models with complex working parts. 3D printing gives students a new perspective withtopographic maps. Science students can study cross-sections of internal organs of the human body and otherbiological specimens. And chemistry students can explore 3D models of molecules and the relationship within

chemical compounds.[115]

Intellectual property

3D printing has existed for decades within certain manufacturing industries and many legal regimes, includingpatents, industrial design rights, copyright, and trademark can apply. However, there is not much jurisprudenceto say how these laws will apply if 3D printers become mainstream and individuals and hobbyist communitiesbegin 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 thedistribution or sale of the printed item. To be allowed to do these things, a person would have to contact theowner and ask for a licence, which may come with conditions and a price.

Patents cover processes, machines, manufactures, and compositions of matter and have a finite duration whichvaries between countries. Therefore, if a type of wheel is patented, printing, using, or selling such a wheel couldbe an infringement of the patent. A report(http://www.patentinsightpro.com/techreports/0214/Tech%20Insight%20Report%20-%203D%20Printing.pdf)on analysis of patenting activity around 3D-Printing from 1990-Current.



Copyright covers an expression[116] in a tangible, fixed medium and often lasts for the life of the author plus

70 years thereafter.[117] If someone makes a statue, they may have copyright on the look of that statue, so ifsomeone sees that statue, they cannot then distribute designs to print an identical or similar statue.

When a feature has both artistic (copyrightable) and functional (patentable) merits, when the question hasappeared 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.[117]

Effects of 3D printing

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 alsopredict that this arc of technological development will counter globalisation, as end users will do much of their

own manufacturing rather than engage in trade to buy products from other people and corporations.[18] The realintegration of the newer additive technologies into commercial production, however, is more a matter of

complementing traditional subtractive methods rather than displacing them entirely.[118]

Space exploration

As early as 2010, work began on applications of 3D printing in zero or low gravity environments.[119] Theprimary concept involves creating basic items such as hand tools or other more complicated devices "ondemand" versus using valuable resources such as fuel or cargo space to carry the items into space.

Additionally, NASA is conducting tests with company Made in Space to assess the potential of 3D printing to

make space exploration cheaper and more efficient.[120] Rocket parts built using this technology have passedNASA firing tests. In July 2013, two rocket engine injectors performed as well as traditionally constructed partsduring hot-fire tests which exposed them to temperatures approaching 6,000 degrees Fahrenheit (3,316 degreesCelsius) and extreme pressures. NASA is also preparing to launch a 3D printer into space; the agency hopes todemonstrate that, with the printer making spare parts on the fly, astronauts need not carry large loads of spares

with them.[121]

Social change

Since the 1950s, a number of writers and social commentators have speculated in some depth about the socialand cultural changes that might result from the advent of commercially-affordable additive manufacturing

technology.[122] Amongst the more notable ideas to have emerged from these inquiries has been the suggestionthat, as more and more 3D printers start to enter people's homes, so the conventional relationship between the

home and the workplace might get further eroded.[123] Likewise, it has also been suggested that, as it becomeseasier for businesses to transmit designs for new objects around the globe, so the need for high-speed freight

services might also become less.[124] Finally, given the ease with which certain objects can now be replicated, itremains to be seen whether changes will be made to current copyright legislation so as to protect intellectualproperty rights with the new technology widely available.

As 3D printers became more accessible to consumers, online social platforms have developed to support the

community.[125] This include websites that allow users to access information such as how to build a 3D printer,as well as social forums that discuss how to improve 3D print quality and discuss 3D printing news, as well as

social media websites that are dedicated to share 3D models.[126][127][128] RepRap is a wiki based website that



was created to hold all information on 3d printing, and has developed into a community that aims to bring 3Dprinting to everyone. Furthermore, there are other sites such as Thingiverse, which was created initially to allowusers to post 3D files for anyone to print, allowing for decreased transaction cost of sharing 3D files. Thesewebsites have allowed for greater social interaction between users, creating communities dedicated around 3Dprinting.

Firearms

Main article: 3D printed firearms

In 2012, the US-based group Defense Distributed disclosed plans to "[design] a working plastic gun that could

be downloaded and reproduced by anybody with a 3D printer."[129][130] Defense Distributed has also designeda 3D printable AR-15 type rifle lower receiver (capable of lasting more than 650 rounds) and a 30 round M16

magazine.[131] The AR-15 has multiple receivers (both an upper and lower receiver), but the legally-controlledpart is the one that is serialised (the lower, in the AR-15's case). Soon after Defense Distributed succeeded indesigning the first working blueprint to produce a plastic gun with a 3D printer in May 2013, the United States

Department of State demanded that they remove the instructions from their website.[132]

After Defense Distributed released their plans, questions were raised regarding the effects that 3D printing and

widespread consumer-level CNC machining[133][134] may have on gun control effectiveness.[135][136][137][138]

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

music, movie or software files."[139]

Internationally, where gun controls are generally tighter than in the United States, some commentators have said

the impact may be more strongly felt, as alternative firearms are not as easily obtainable.[140] European officials

have noted that producing a 3D printed gun would be illegal under their gun control laws,[141] and that criminalshave access to other sources of weapons, but noted that as the technology improved the risks of an effect would

increase.[142][143] Downloads of the plans from the UK, Germany, Spain, and Brazil were heavy.[144][145]

Attempting to restrict the distribution over the Internet of gun plans has been likened to the futility of preventing

the widespread distribution of DeCSS which enabled DVD ripping.[146][147][148][149] After the US governmenthad Defense Distributed take down the plans, they were still widely available via The Pirate Bay and other file

sharing sites.[150] Some US legislators have proposed regulations on 3D printers, to prevent them being used for

printing guns.[151][152] 3D printing advocates have suggested that such regulations would be futile, could cripplethe 3D printing industry, and could infringe on free speech rights, with early pioneer of 3D printing Professor

Hod Lipson suggesting that gunpowder could be controlled instead.[153][154][155]

Automotive use

In early 2014, the Swedish supercar manufacturer, Koenigsegg, announced the One:1, a supercar that utilisesmany components that were 3D printed. In the limited run of vehicles Koenigsegg produces, the One:1 has side-mirror internals, air ducts, titanium exhaust components, and even complete turbocharger assembles that have



been 3D printed as part of the manufacturing process.[156]

Materials innovations

Consumer grade 3D printing has resulted in new materials that have been developed specifically for 3D printers.For example, filament materials have been developed to imitate wood, in its appearance as well as its texture.Furthermore, new technologies, such as infusing carbon fibre into printable plastics, allowing for a stronger,lighter material. In addition to new structural materials that have been developed due to 3D printing, newtechnologies have allowed for patterns to be applied directly to 3D printed parts.

See also

References

3D modelling

3D scanner

3D Printing Marketplace

Additive Manufacturing File Format

List of common 3D test models

List of emerging technologies

Mass customisation

Molecular assembler

Organ-on-a-chip

Self-replicating machine

Tissue engineering

Milling (machining) computer controlled machine production

Numerical control DIY machine production

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Further reading

Stephens, B.; Azimi, P.; El Orch, Z.; Ramos, T. (2013). "Ultrafine particle emissions from desktop 3D

printers". Atmospheric Environment 79: 334. doi:10.1016/j.atmosenv.2013.06.050

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Easton, Thomas A. (November 2008). "The 3D Trainwreck: How 3D Printing Will Shake Up

Manufacturing". Analog 128 (11): 5063.

Wright, Paul K. (2001). 21st Century Manufacturing. New Jersey: Prentice-Hall Inc.

The involvement of recycling material (http://www.absplastic.eu/3d-printers-that-use-recycled-plastic/)

(http://sacramento.cbslocal.com/2013/05/08/sen-leland-yee-proposes-regulations-on-3-d-printers-after-gun-

test/). CBS Sacramento. 2013-05-08. Retrieved 2013-10-30.

152. ^ Schumer Announces Support For Measure To Make 3D Printed Guns Illegal

(http://newyork.cbslocal.com/2013/05/05/schumer-announces-support-for-measure-to-make-3d-printed-guns-

illegal)

153. ^ "Four Horsemen of the 3D Printing Apocalypse" (http://makezine.com/27/doctorow/). Makezine.com. 2011-

06-30. Retrieved 2013-10-30.

154. ^ Ball, James (10 May 2013). "US go

Documents

3D printing.pdf