3D printing Technologies

3D Printing Technologies

Here you will find information about the different types of 3D printing processes as well as the various 3D printers used for each technology such as:

Stereolithography (SLA)

Stereolithography (SLA) is a resin 3D printing or additive manufacturing process that uses a vat of photopolymer resin that can be cured. The build plate moves down in small increments and the liquid polymer is exposed to light where the UV laser draws a cross section layer by layer. The process repeats until a model has been created. The object is 3D printed by pulling the object out of the resin (bottom up) which creates space for the uncured resin at the bottom of the container and can then form the next layer of the object. Another way is to 3D print the object by pulling it downward into the tank with the next layer being cured on the top.

These photopolymer parts do not have the strength of SLS or FDM parts, but can typically achieve much higher levels of detail. As the photopolymer is UV sensitive, these products are susceptible to deforming and changing colors in sunlight.

SLA is commonly used to generate highly detailed artwork, non-functional prototypes, and can be used to make molds in investment casting applications.

3D Systems iPro 8000

EnvisionTEC Perfactory 4 DSP

One of 3 SLA 3D printers in the Production range.

One of 5 printers in the Perfactory Standard Family.

EnvisionTEC ULTRA 3SP

EnvisionTEC Xtreme 3SP

One of 3 printers in the Ultra Family.

One of 2 printers in the Industrial Printer Family.

For more information about the 3D printers, please check out ourGuide to Professional 3D Printers.

PolyJet MultiJet

Similar to Stereolithography, the high-quality 3D printer PolyJet and MultiJet processes use a UV light to crosslink a photopolymer. However, rather than scanning a laser to cure layers, a printer head jets tiny droplets of the photopolymer (similar to ink in an inkjet printer) in the shape of the first layer. The UV lamp attached to the printer head crosslinks the polymer and locks the shape of the layer in place. The build platform then steps down one layer thickness and more material is deposited directly on the previous layer. This is process is repeated until the part has completed printing.

PolyJet 3D printers, such as the Stratasys Objet 3D printers, are capable of highly complex and high resolution parts with fine features, but lack the strength of SLS and FDM parts. Combining two or three materials in specific concentrations and microstructures, this technology allows to produce a range of materials with varying translucency, rigidity, thermal resistance or color. Using this process, a single part can contain materials with diverse physical and mechanical properties ranging from rubber-like flexibility to ABS-like rigidity. Similar to SLA, the photopolymer is vulnerable to sunlight and heat, and the material can creep over time.

Poly-jet printing is a great process for developing fully assembled prototypes and complex and detailed geometries with multiple material properties.

Stratasys Objet30 Pro

Stratasys Objet500 Connex3

Stratasys Objet1000

One of 10 PolyJet 3D printers in the Design Series.

One of 10 PolyJet 3D printers in the Design Series.

One of 10 PolyJet 3D printers in the Professional line.

3D Systems Projet 3510SD

3D Systems Projet 5500X

One of 10 MultiJet 3D printers in the Professional line.

One of 10 MultiJet 3D printers in the Professional line

For more information about the 3D printers, please check out ourGuide to Professional 3D Printers.

Digital Light Processing (DLP)

Digital Light Processing is a 3d printing process where a projector is used to cure photopolymer resin. Very similar to SLA where the only difference is that instead of a UV laser to cure the photopolymer resin, a safelight (light bulb) is used. Objects are created the same as SLA with the object being either pulled out of the resin which creates space for the uncured resin at the bottom of the container and to form the next layer of the object or down into the tank with the next layer being cured on the top.

Objects that are printed with Digital Light Processing have less visible layers versus other processes such as FDM/FFF. Compared with SLA, DLP can have faster build speeds due to a single layer being created in one singular digital image whereas with SLA, the UV laser has to scan the vat with a single point (trace out the object layer).

Also, the same photopolymer resins that can be used with SLA, can be used for DLP 3D Printing. Objects printed with this process have the same strengths and weaknesses.

Similar to SLA, DLP is commonly used to generate highly detailed artwork, non-functional prototypes, and can be used to make molds in investment casting applications.

3D Systems ProJet- 3510 CPX

3D Systems Projet 5500X

One of 4 printers in the Professional line intended for moulds and casting.

One of 4 Rapid Shape printers made especially for jewelry casting.

For more information about the 3D printers, please check out ourGuide to Professional 3D Printers.

Selective Laser Sintering (SLS)

SLS is an Additive Manufacturing method that uses a powder bed fusion process to build 3D parts.

Powdered polymer build material, typically nylon, is transferred from containers holding fresh powder onto the build stage in the process chamber with a recoating tool. A laser then selectively scans the thin layer of powder, sintering together powder particles in the shape of the cross-section of the first layer of the 3D part. The build platform then descends one layer depth and the recoater transfers more fresh powder from the hopper to the surface of the first layer. Just like the first layer, the second cross-section of the 3D model is scanned and sintered. The laser scanning process simultaneously generates the current layer and adjoins it to the previous layer, making a solid part.

Compared to other additive manufacturing processes such as stereolithography (SLA) and Fused Deposition Modeling (FDM) or Fused Filament Fabrication (FFF), SLS does not require support structures since the powder acts as self supporting material. This allows intricate and complex geometries to be constructed.

The applications for this 3D printing process are designs with moving parts, prototypes, consumer products, architectural models, hardware, electronics housing, sculptures, promotional items and more.

3D Systems sPro 230

EOS Formiga P110

EOS INT P760

One of 5 printers in the Production line of SLS printers.

One of 4 plastic SLS machines from EOS.

One of 4 plastic SLS machines from EOS.

For more information about the 3D printers, please check out ourGuide to Professional 3D Printers.

Metal 3D Printing

Direct Metal Laser Sintering (DMLS)

The applications for this 3D printing process are finished parts from various industries such as aerospace and defense, medical industry, creation of molds, etc.

Direct Metal Laser Sintering or DMLS is an additive manufacturing technique for 3D printing metal that was developed by EOS. It uses a laser as a power source in order to sinter metal powder by aiming a laser and tracing a cross section of the object layer by layer. Direct Metal Laser SIntering is similar to the selective laser sintering process.

The build changer has a material dispensing platform and a build platform along with a re-coater blade which is used to move new powder over the build platform. The process fuses metal powder into a solid part by melting it locally using the focused laser beam where it traces the cross section of the object layer by layer. This allows for highly complex geometries to be developed.

DMLS has many benefits over traditional manufacturing techniques since no special tooling is required and parts can be built fairly quickly. DMLS allows for more rigorous testing of prototypes. DMLS can use most alloys and prototypes can be functional hardware made out of the same material as production parts.

Electron Beam Melting (EBM)

Electron beam melting or EBM is a type of additive manufacturing that is classified as a power bed fusion technique that was originally patented and developed by Arcam AB. EBM uses an electron beam as the power source instead of a laser to 3D print metal. An electron beam melts metal powder layer by layer in a high vacuum and can achieve full melting of the metal powder. This method can produce fully dense metal parts and can retain the characteristics of the material.

The Electron Beam Melting process can produce metal parts with 100% density and its material properties are much better than cast metals. The EBM process takes place in a vacuum which makes this process perfect for manufacturing reactive materials with a high affinity for oxygen. This process also operates at higher temperatures (up to 1000C).

Some of the materials used with this technology are Titanium Alloys which make it an excellent choice for medical implant market, copper, niobium, AL 2024, bulk metallic glass, stainless steel, and titanium aluminide.

Compared to DMLS, EBM has a superior build rate because of its higher energy density and scanning method.

3D Systems ProX300

Arcam Q20

EOS M 400

One of 5 printers in the Production line of DMLS metal printers. This one is the biggest, highest-end printer. Comes with automatic material loading and recycling system.

One of 3 Electron Beam Melting (EBM) machines.


One of 2 metal sintering printers. This one is based on a modular concept available with setup and process stations with automated unpacking station module in the future.

Exone M-Flex

Renishaw AM250

Concept Laser LaserCUSING- M2 CUSING

One of 3 metal printers.

The only 3D printer available from Renishaw which also produces a vacuum casting machine.

One of 2 metal printers from Concept Laser.

For more information about the 3D printers, please check out ourGuide to Professional 3D Printers.

Full Color 3D Printing

Binder Jetting

Binder Jetting, also known as full color 3D printing or Inkjet Powder Printing is an additive manufacturing process that is popular since you can have detailed 3D prints with color. An automated roller is used to spread a layer of powder onto the build platform. Excess powder is pushed to the sides and ensures that the bed is filled with a layer of packed powder. On a fast axis, the print heads apply a liquid binder and color simultaneously to create a cross section of the object on the powder. The same way an inkjet paper printer works only with this process, instead of paper, powder is the medium. The process is then repeated where the bed lowers and a layer of powder is rolled across the top and the print heads dispense liquid binder and color until the object is created. With this process, there is no need for support since the powder is self supporting. Compared to FDM/FFF, this process requires further post processing techniques such as vacuuming of the excess powder, depowdering the object using compressed air, then infiltrating the object with cyanoacrylate (super glue)

Selective Deposition Lamination

Selective Deposition Lamination (SLD) is a 3D printing process using paper. This process is similar to Laminated Object Manufacturing (LOM) rapid prototyping method. The process involves layers of adhesive coated paper (or plastic or metal laminates) that are successively glued together with a heated roller and cut to shape with a laser cutter layer by layer. A roller with the material moves each new sheet of material over the last and repeats the process until the object is completed.

Materials to 3D print using this process is relatively low cost since you can use off the shelf copy paper from any office store. Since 3D printed models from paper have wood like characteristics, they can be further processed using some wood finishing techniques.

Triple-jetting technology (PolyJet)

Triple-jetting technology, used in Stratasys Objet500 Connex3, is PolyJet 3D printing at its most advanced. This technology allows precise printing with three materials and thus makes three-color mixing possible. To know more about this technology, you can refer to previous paragraph aboutPolyJet MultiJet.

The applications for these 3D printing processes are figurines, character concept, decorative objects, architectural mockups, etc.

For more information about the 3D printers, please check out ourGuide to Professional 3D Printers.

Fused Deposition Modeling/Fused Filament Fabrication (FDM/FFF)

The applications for this 3D printing process are Concept Parts, Functional Models, Prototypes, Manufacturing Tooling and Molding, End Use Parts.

Fused Deposition Modeling (FDM) or Fused Filament Fabrication (FFF) is probably the most popular printing process due to the number of printers available on the market from the 3D Printer Kit versions to the Professional 3D printer (or high-quality 3D printer). FDM is an affordable 3D printing process versus other 3D printing technologies.

FDM is an additive manufacturing process that is great for rapid prototyping concept parts, functional models, manufacturing tooling and molding, and end use parts. This process works by material being melted and extruded through a nozzle to 3D print a cross section of an object each layer at a time. The bed lowers for each new layer and repeats until the object is completed. Layer height determines the quality of the 3D print. Some FDM printers can have two or more print heads that can print in multiple different colors and use support for overhanging areas of a complex 3D print. Support material and rafts are sometimes troublesome to remove cleanly from the object itself.

Many different materials exist for this type of printing process. It varies between the industrial versus the consumer version. The most common however are ABS, PLA and polycarbonate. Unlike ABS, PLA is biodegradable and is popular due to it being non-toxic. There is also dissolvable materials such as PVA which are used for support.