Glossary

3D printing

General term referring to computer-controlled machines that precisely deposit minute qualities of matter, sequentially, to form recognizable shapes.

4D printing

Term coined by MIT researcher Skylar Tibbits to refer to 3D printed matter that, over time (the 4th D) reshapes itself in response to water, light, or other stimuli.

Additive manufacturing

Essentially the same as 3D printing but in an industrial milieu.

Binder jetting

3D printing variant that relies on binder (adhesive) rather than intense heat to hold, for example, sand in precise shapes. Heat is frequently used in secondary processes such as sintering or infiltration.

Bioprinting

An emerging class of technologies looking to assemble components of tissue with extruders and other 3D printing technologies, sometimes using live cells suspended in a hydrogel.

Build

The outcome of a set of layer-by-layer depositions of material as directed by a computer file.

CAD

Computer Assisted Design software, frequently the origin of a 3D printed part. One alternative is to 3D scan an existing thing and replicate it.

Composite

A material made up of different material, such as plastic filament infused with carbon fibers.

DMLM

Direct Metal Laser Melting is a 3D printing technology used for powder-bed fabrication in which the metal is fully melted into a tiny liquid pool, distinct from DMLS.

DMLS

Direct Metal Laser Sintering only partially melts the metal powder particles into more of a jelly than a fully liquid state. See DMLM.

Filament

Strings of thermoplastic polymers fed into several varieties of 3D printers.

FDM

Fused Deposition Modeling is a proprietary term owned by Stratasys to refer to extrusion-based 3D printing, often in consumer-grade machines.

FFF

Fused Filament Fabrication is a generic term referring to the same techniques indicated by FDM.

Material jetting

Hundreds of microscopic jets deposit photopolymers under computer control in full color and with very high surface quality but relatively low structural strength.

Powder

Plastic, ceramic, or metal (both pure and alloys) that is laid down in precisely thin layers by a wiper to provide both feedstock for fusing and support for the build in process. Excess material is removed at the end of a build using compressed air.

Reverse engineering

The process whereby the design information for an existing part that lacks digital documentation is recreated, often via some form of 3D scanning.

SLA

Stereolithography Apparatus was the original additive manufacturing technique, developed and commercialized in the late 1980s. It uses light-sensitive resins fused in thin layers by various forms of light.

SLM

Selective Laser Melting is a variety of DMLM when applied to pure metals rather than alloys.

SLS

Selective Laser Sintering can be applied to metals as well as to glass, polymers, and ceramics. As in DMLS, the powder is not fully melted.

Support structure

In both polymer and metal builds, support structures are pieces extraneous to the final shape that are necessary for either supporting a horizontal element during the build and/or to help conduct heat to the build platform to prevent warping and other forms of thermal distortion.

Topology optimization

A software process whereby an existing structure is given new, reduced shape(s) through the mathematic elimination of material that is not essential to the part’s function and context.