Additive Manufacturing Glossary and Acronyms

The following are key terms used in Wohlers Report 2022 and across the additive manufacturing and 3D printing industry. Most of these terms conform to the ISO/ASTM 52900 terminology standard. An asterisk (*) by a term denotes and ISO/ASTM 52900 standard definition.

3D digitizing – Same as 3D scanning.

3D printer* – Machine used for 3D printing.

3D printing* – Fabrication of objects through the deposition of a material using a print head, nozzle, or another printer technology. Term often used in a non-technical context synonymously with additive manufacturing; until present times, this term has in particular been associated with machines that are low end in price and/or overall capability.

3D scanning* – Method of acquiring the shape and size of an object as a 3D representation by recording x, y, z coordinates on the object’s surface and through software converting the collection of points into digital data.

3MF – Additive manufacturing file format used to describe color, textures, materials, and other characteristics of a 3D model. Ongoing development of the file format is led by the 3MF Consortium, which was initiated by Microsoft and other companies in 2015.

ABS – Acrylonitrile butadiene styrene; a thermoplastic polymer with high-impact resistance and toughness.

additive layer manufacturing – Same as additive manufacturing.

additive manufacturing* – Process of joining materials to make parts from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies; historical terms are additive fabrication, additive processes, additive techniques, additive layer manufacturing, layer manufacturing, solid freeform fabrication, and freeform fabrication.

additive process – Same as additive manufacturing.

additive system* – Additive manufacturing system, additive manufacturing equipment, machine and auxiliary equipment used for additive manufacturing.

AM – Additive manufacturing

AMF* – Additive Manufacturing File format for communicating additive manufacturing model data including a description of the 3D surface geometry with native support for color, materials, lattices, textures, constellations, and metadata.

as built* – The state of parts made by an additive process before any post-processing, besides, if necessary, the removal from a build platform as well as the removal of support and/or unprocessed feedstock.

ASTM International – International standards organization, formerly known as American Society for Testing and Materials.

B2B – Business to business.

B2C – Business to consumer.

batch* – Defined quantity of feedstock with uniform properties and composition.

binder jetting* – Additive manufacturing process in which a liquid bonding agent is selectively deposited to join powder materials.

BJT – Binder jetting.

bounding box* – Orthogonally oriented minimum perimeter cuboid that can span the maximum extents of the points on the surface of a part.

build chamber* – Enclosed location within the additive manufacturing system where the parts are fabricated.

build envelope* – Largest external dimensions of the x-, y-, and z-axes within the build space where parts can be fabricated.

build space* – Location where it is possible for parts to be fabricated, typically within the build chamber or on a build platform.

build volume* – Total usable volume available in the machine for building parts.

CAD – Computer-aided design; the use of computers for the design of real or virtual objects.

CAE – Computer-aided engineering; CAE software offers capabilities for engineering simulation and analysis, such as determining a part’s strength or heat-transfer capacity.

CAM – Computer-aided manufacturing; typically refers to systems that use surface data to drive CNC machines, such as digitally driven mills and lathes, to produce parts, molds, and dies.

ceramic – Inorganic and non-metallic crystalline material with high compression strength and low shear and tensile strength.

cermet – Material made from ceramic and metal with heat-resistance properties.

CIM – Ceramic injection molding.

CNC – Computer numerical control; computer-controlled machines include mills, lathes, and flame cutters.

CT – Computed tomography; CT scanning is a method of capturing the internal and external structure of an object using ionizing radiation. A CT scan creates a series of two-dimensional gray-scale images that can be used to construct a 3D model.

cure* – Change the physical properties of a material by means of a chemical reaction.

DED – Directed energy deposition.

DfAM – Design for additive manufacturing.

digital light processing – A display device that creates an image using an array of micromirrors; each mirror represents one or more pixels in the projected image.

direct metal deposition – A trade name used by DM3D for the company’s directed energy deposition technology.

direct metal laser sintering – A trade name used by EOS for the company’s metal powder bed fusion technology.

directed energy deposition* – Additive manufacturing process in which focused thermal energy is used to fuse materials by melting as they are being deposited. “Focused thermal energy” means that an energy source (e.g., laser, electron beam, or plasma arc) is focused to melt the materials being deposited.

DLP – Digital light processing, a technology developed by Texas Instruments.

DMD – Direct metal deposition.

DMLS – Direct metal laser sintering.

EBM – Electron beam melting.

EDM – Electrical discharge machining; a method of machining that removes material with a series of electrical current discharges between a tool electrode and a workpiece.

elastomer – Amorphous polymers with elasticity and low stiffness.

electron beam melting – A trade name used by GE Additive for Arcam electron-beam-based metal powder bed fusion technology.

extrusion nozzle* – Component with an orifice through which feedstock is extruded.

facet* – Three- or four-sided polygon that represents an element of a 3D polygonal mesh surface or model. Triangular facets are used in the file formats most significant to AM: AMF and STL files; however, AMF files permits a triangular facet to be curved.

FDM – Fused deposition modeling.

feedstock* – Bulk raw material supplied to the additive manufacturing building process.

fully dense* – State in which the material of a fabricated part is without significant content of voids.

fused deposition modeling – A trade name used by Stratasys for the company’s material extrusion technology.

fusion* – Act of uniting two or more units of material into a single unit of material.

HIP – Hot isostatic pressing.

hot isostatic pressing – Uses heat and isostatic pressure to reduce or eliminate the porosity in metals and increase the density of ceramics.

hybrid manufacturing system – Manufacturing system that uses both additive and subtractive technologies.

ISO – International Standards Organization; more widely known as the International Organization for Standardization.

laser sintering* – Powder bed fusion process used to produce objects from powdered materials using one or more lasers to selectively fuse or melt the particles at the surface, layer upon layer, in an enclosed chamber.

layer additive manufacturing – Same as additive manufacturing.

LS – Laser sintering.

machine coordinate system* – Three-dimensional coordinate system defined by a fixed point on the build platform; defined by the machine manufacturer.

maker – A member of a technology-based do-it-yourself (DIY) community.

material extrusion* – Additive manufacturing process in which material is selectively dispensed through a nozzle or orifice.

material jetting* – Additive manufacturing process in which droplets of feedstock material are selectively deposited. Example materials include photopolymer and wax.

MCAD – Mechanical computer-aided design; the use of CAD to design mechanical parts and assemblies.

MEMS – Microelectromechanical systems.

metrology – Science of measurement.

MEX – Material extrusion.

MIM – Metal injection molding.

MJF – Multi Jet Fusion technology from HP.

MJT – Material jetting.

MRI – Magnetic resonance imaging; alternative to CT scanning that offers better soft-tissue contrast; MRI does not use ionizing radiation.

multi-step process* – Additive manufacturing process in which parts are fabricated in two or more operations; the first step typically provides the basic geometric shape, and the following consolidates the part to the fundamental properties of the intended material.

near net shape* – Condition where the parts require little post-processing to meet dimensional tolerance.

nesting* – Situation when parts are made in one build cycle and are located such that their bounding boxes, arbitrarily oriented or otherwise, overlap.

NSF – National Science Foundation; U.S. government funding agency.

OEM – Original equipment manufacturer.

PA – Polyamide; a family of thermoplastic polymers often used for powder bed fusion systems.

PAEK – Polyaryletherketone; a high-melting-temperature thermoplastic polymer; a member of the polyaryletherketone family.

PBF – Powder bed fusion.

PBT  – Polybutylene terephthalate; a strong thermoplastic polymer used as an insulator and is resistant to solvents.

PC – Polycarbonate; a family of thermoplastic polymers that are highly formable with high-impact resistance.

PCL – Polycaprolactone; biodegradable polyester used to produce specialty polyurethanes.

PEEK – Polyether ether ketone; a high-melting-temperature thermoplastic polymer; a member of the polyaryletherketone family.

PEI – Polyethylenimine; a polymer used for adhesives, detergents, and cosmetics.

PEKK – Polyetherketoneketone; a high-melting-temperature thermoplastic polymer; a member of the polyaryletherketone family.

PHA – Polyhydroxyalkanoate; polyesters produced naturally from bacterial fermentation of lipids or sugar; biodegradable and used to produce bioplastics.

photopolymer – A thermoset polymer that changes properties when exposed to ultraviolet or visible light; typically, a photopolymer changes from liquid to solid during photopolymerization.

PIM – Plastic injection molding; popular method of molding parts from thermoplastic materials such as polypropylene, polyamide (nylon), polycarbonate, ABS, polyethylene, and polystyrene.

PLA – Polylactic acid; a thermoplastic polymer that is biodegradable and often derived from renewable sources such as corn starch, sugar cane, or tapioca roots.

PLLA – Poly-L-lactic acid (see PLA).

PMMA – Polymethyl methacrylate; a thermoplastic polymer that is used in Voxeljet’s binder jetting process.

polymer – Material made up of large molecules that consist of repeating molecular units.

porosity* – Presence of small voids in a part, making it less than fully dense; typically quantified as a ratio and expressed as a percentage.

post-processing* – One or more process steps taken after the completion of an additive manufacturing build cycle to achieve the desired properties in the final product.

powder bed fusion* – Additive manufacturing process in which thermal energy selectively fuses regions of a powder bed.

PP – Polypropylene; a thermoplastic polymer used in a range of applications.

PPS – Polyphenylene sulfide; an organic polymer often used for making filter fabric.

process parameters* – Operating parameters and system settings used during a build cycle.

production run* – All parts produced in one build cycle or sequential series of build cycles using the same feedstock batch and process conditions.

prototype* – Physical representation of all or a component of a product that, although limited in some way, can be used for analysis, design, and evaluation.

prototype tooling* – Molds, dies, and other devices used for prototyping purposes; sometimes referred to as bridge tooling or soft tooling.

rapid prototyping* – Application of additive manufacturing intended for reducing the time needed for producing prototypes. Historically, rapid prototyping (RP) was the first commercially significant application for additive manufacturing and has therefore been commonly used as a general term for this type of technology.

rapid tooling* – Application of additive manufacturing intended for the production of tools or tooling components with reduced lead times as compared to conventional tooling. Rapid tooling may be produced directly by the additive manufacturing process or indirectly by producing patterns that are in turn used in a secondary process to produce the actual tools.

resolution* – Dimensions of the smallest part feature that can be controlled when built.

reverse engineering – A method of creating a digital representation from a physical object to define its shape, dimensions, and internal and external features.

selective laser melting – A generic name for metal powder bed fusion.

selective laser sintering – A trade name used by 3D Systems for the company’s polymer powder bed fusion technology.

SFF – Solid freeform fabrication; another name for additive manufacturing.

sheet lamination* – Additive manufacturing process in which sheets of material are bonded to form a part.

SHL – Sheet lamination.

single-step process* – Additive manufacturing process in which parts are fabricated in a single operation where both geometric shape and material properties are achieved simultaneously.

SLA – Stereolithography apparatus.

SLM – Selective laser melting.

SLS – Selective laser sintering.

SMEs – Small- and medium-sized enterprises.

solid model – 3D CAD representation somewhat analogous to using material, such as wood or plastic, to create a shape. Many solid-modeling software products use geometric primitives, such as cylinders and spheres, and features such as holes and slots, to construct 3D shapes. Solid models are preferred over surface models for additive manufacturing because they define a closed, “watertight” volume—a requirement of most additive manufacturing systems.

STEAM – Science, technology, engineering, art, and mathematics.

STEM – Science, technology, engineering, and mathematics; often used in association with education policy and curriculum development in schools to help improve competitiveness.

stereolithography – See vat photopolymerization.

STL – File format for 3D model data used by machines to build physical parts. STL is the de facto standard interface for additive manufacturing systems. STL originated from the term stereolithography. The STL format uses triangular facets to approximate the shape of an object, listing the vertices, ordered by the right-hand rule, and unit normals of the triangles, and excludes CAD model attributes.

support* – Structure separate from the part geometry that is created to provide a base and anchor for the part during the building process.

surface model* – Mathematical or digital representation of an object as a set of planar or curved surfaces, or both, that can, but not necessarily have to represent a closed volume.

thermoplastic – A polymer that can be repeatedly melted, cooled, and solidified.

thermoset – A polymer that is permanently cured once polymerized.

tool, tooling – Mold, die, or another device used in various manufacturing processes such as plastic injection molding, thermoforming, blow molding, die casting, sheet metal stamping, hydroforming, forging, composite layup, machining, and assembly fixtures.

topological optimization – Same as topology optimization.

topology optimization – Use of mathematics to optimize the strength-to-weight ratio of a design. The approach minimizes the use for a given set of load and constraint conditions.

TPE – Thermoplastic elastomer; polymer that exhibits exceptional elastomeric properties.

TPU – Thermoplastic polyurethane; a class of polyurethane plastics (thermoplastic elastomers) that share properties of elasticity, transparency, and resistance to oil and grease.

triangulation – Method of inferring the location of a point on a surface by projecting light onto the surface and observing that light from a different angle or orientation.

vat photopolymerization* – Additive manufacturing process in which liquid photopolymer in a vat is selectively cured by light-activated polymerization.

virgin* – Condition of feedstock from a single manufacturing lot before being applied to the additive manufacturing process.

voxel – Volume element; objects and three-dimensional datasets can be divided into an array of discrete elements, called voxels, on a regular grid in three-dimensional space.

VPP – Vat photopolymerization.

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