Types of 3D Printing Technology – Understanding the Difference

What Types of 3D Printers Are There?

3D printing (also known as additive manufacturing) is a process that creates 3-dimensional physical objects from a digital model. 3D printers are machines that specialize in additive manufacturing i.e. they build parts by adding layers of material in successive layers.

3D printing has application in a variety of industries including prototyping specialized parts (dental, aerospace, automotive, housing, industrial, etc.).

There are many 3D printers in the market that let you create 3D objects. In this article, we’ll go over 10 of the most common 3D printing technologies to help you identify the one that meets your particular needs.

  • Stereolithography (SLA)
  • Selective Laser Sintering (SLS)
  • Direct Metal Laser Sintering (DMLS) / Selective Laser Melting (SLM)
  • Fused Filament Fabrication (FFF), also called Fused Deposition Modeling (FDM)
  • Digital Light Processing (DLP)
  • Electron Beam Melting (EBM)
  • Multi Jet Fusion (MJF)
  • Binder Jetting
  • Material Jetting
  • Carbon Digital Light Synthesis™ (DLS)

Stereolithography (SLA)

Stereolithography is a rapid prototyping technique that uses a liquid photosensitive polymer and an ultraviolet laser beam to create a solid object. The build platform is submerged in a tank filled with curable liquid photopolymer resin. The UV light maps the desired pattern of the object, thus hardening the material.

SLA printing uses support structures that are attached to the build platform to prevent the part from deforming or curling.

SLA printers can print high-quality prototype parts with a smooth surface finish and fine details. However, SLA printed parts need to be bathed in a solvent (isopropyl alcohol) to remove uncured liquid resin from their surface.

Selective Laser Sintering (SLS)

Selective Laser Sintering (SLS) is a powder bed fusion technique that uses a high energy source to selectively fuse powedered thermoplastic material (for example, metal, plastic, ceramic, or glass) to build a 3D printed part.

The high power laser maps the cross-section of the surface of powdered material based on a 3D model, fusing it into a solid layer. The build platform then lowers by the height of one layer, and a new layer of thermoplastic material is deposited on top. This process is repeated layer by layer until the physical object is manufactured.

SLP 3D printing results in robust and extremely detailed printed parts. It is used for creating functional, accurate prototypes and production parts.

Proper protective gear should be used for SLS printing as is powered raw material contains very small particles which can be dangerous if inhaled.

Direct Metal Laser Sintering (DMLS) / Selective Laser Melting (SLM)

Direct metal laser sintering (DMLS) is a 3D printing method that builds 3D objects by melting powdered metal using a laser beam. Almost any metal alloy can be used in DMLS 3D printing.

It is used for manufacturing functional prototypes and end-use metal parts with fine details.

DMLS printing is expensive as you need a high-powered laser light source. Similarly, the high temperatures may cause the printed parts to warp.

Fused Filament Fabrication (FFF)

Fused filament fabrication (FFF) or fused deposition modeling (FDM) is the most widely used additive manufacturing process that creates 3d printed parts by depositing layers of melted plastic filament in a pattern layer by layer until the entire object is created. Common printing materials used in FFF include PLA and ABS.

This form of 3D printing is useful for prototyping and modeling, and has applications in many industries including automotive, aerospace, and medical.

However, FFF printers are not ideal for printing parts with complex geometries due to design limitations such as warping, layer shifting, and low resolution. FFF is also slower compared to other extrusion-based technologies.

Digital Light Processing (DLP)

Digital light processing (DLP) is an additive manufacturing technology where liquid photopolymer resin is solidified layer-by-layer. DLP 3D printers use a digital micromirror device (DMD) to reflect and focus UV light on the surface of photosensitive materials, resulting in quicker solidification.

Both DLP and SLA technologies use liquid resin for 3D printing, however, they employ different light sources. DLP uses a digital light projector, whereas, SLA uses a UV laser beam.

DLP printing is useful for printing functional prototypes with complex designs faster than SLA.

Unlike SLA, where the laser beam moves from one point to another to solidify a single layer, the entire image is flashed at once. This allows the entire layer to harden faster, so the printer can move on the print the next layer.

However, DLP parts require post-processing to achieve the same surface quality as SLA printed parts.

Electron Beam Melting (EBM)

Electron beam melting (EBM) is a highly-advanced additive manufacturing technique that uses a high-powered electron beam to fuse metal powder into the desired object.

This process builds layers by heating the entire powder bed to temperatures specific to the material used. As a result, parts are printed without residual stress, preventing them from distorting and warping.

EBM printing offers a cost-effective way to produce metal parts with material waste. It is commonly used for high-end prototyping and building products with complex geometric structures.

However, EBM printed parts have surface roughness similar to sand casting and may require surface finishing to smooth out the surface.

Multi Jet Fusion (MJF)

Multi jet fusion (MJF) is an inkjet printing technology that uses a layer of material powder (for example, Nylon PA12) as a base to build a part. A thin layer of material powder is deposited on the part bed. An inkjet head passes over the dispersed material and applies detailing and fusing agents onto it. An infrared light source is then moved across the print bed which melts the fusion agent and the material powder below it and the detailing agent (and the material powder below it).

This process results in functional parts suitable for end-use. It is commonly used for manufacturing parts with fine feature resolution at much faster build speeds.

There are two common methods differentiated by the fusion source: DMLS/SLS use laser, whereas multi jet fusion uses inkjet to promote sintering.

Binder Jetting

Binder jetting is an additive manufacturing process in which thin layers of powdered material are selectively applied to a powder bed and bonded to a liquid bonding agent. The powder particles adhere together to cause layer solidification. This process is repeated layer by layer until the entire product is created.

It is a zero-waste 3D printing process as any used powdered material can be reused to build parts in the future. Similarly, binder jetting uses less material than other methods such as SLA and FFF printing.

Binder jetted parts don’t warp because neither heating nor cooling are involved in the process.

However, these parts have weaker mechanical properties (i.e low part strength and parts might elongate or break at lower forces).

Material Jetting

In material jetting, a printhead deposits droplets of photopolymers onto a build bed, and then UV light is used to instantly cure the liquid material.

Material jetting is used to produce parts with high accurate layer resolution (down to 14 microns) and a smooth surface finish. Secondly, on-demand material dropping results in low wastage.

Material jetting machines are expensive and the print time is slow compared to other 3D printing technologies.

Carbon Digital Light Synthesis (DLS)

Digital light synthesis (Carbon DLS)™ is a resin-based 3D printing process that uses ultraviolet light to cure the liquid plastic resin. UV images are projected through an oxygen-permeable window through the tank filled with photosensitive resin. The UV source cures a layer, and the build platform rises to allow the curing of the next layer. This process repeats until the entire part is built.

The DLS process uses Carbon’s breakthrough Continuous Liquid Interface Production™, or CLIP™ to build functional, end-use parts with superior dimensional accuracy and premium surface finish.

Need functional parts and prototypes that can meet your industry-specific criteria? Check out industrial 3D printing with Carbon to see how you can enhance your parts’ quality and costs.

Upgrade Your 3D Printing with Carbon

There are many 3D printing technologies available in the market. The 3D printer you choose for your manufacturing needs will depend on your particular requirements.

Carbon 3D printers let you rapidly build your product’s prototypes with accuracy and reliability.

Bring your ideas to production faster with Carbon!

3D as It’s Meant to Be

Interested in utilizing Carbon to accelerate product development? Reach out to us at sales@carbon3d.com to learn more!