Additive Manufacturing Glossary

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A

ADDCAAM

ADDCAAM (Computer-Aided Additive Manufacturing) is ADDMAN’s proprietary software platform that improves the structural performance of Fused Deposition Modeling (FDM) by optimizing toolpaths during the printing process. Rather than relying on conventional slicing strategies, ADDCAAM uses advanced toolpath optimization and interlocking bead placement to improve load distribution and reduce porosity within printed components. The software enables manufacturers to produce stronger FDM parts using existing equipment without modifying printer hardware.

Related Terms: FDM, Toolpath, Toolpath Optimization

Additive Manufacturing

Additive Manufacturing (AM) is a group of manufacturing processes in which three-dimensional parts are produced by adding material layer by layer from a digital model. Unlike subtractive manufacturing processes that remove material from a workpiece, additive manufacturing builds components by selectively depositing, melting, fusing, or curing material only where needed. Depending on the technology, additive manufacturing can process metals, polymers, ceramics, and composite materials for applications ranging from prototyping and tooling to qualified production components.

Today, additive manufacturing encompasses multiple process families—including powder bed fusion, material extrusion, vat photopolymerization, binder jetting, and material jetting—each suited to different materials, geometries, performance requirements, and production volumes. It is often used alongside conventional manufacturing methods such as CNC machining, injection molding, and assembly as part of an integrated manufacturing strategy.

Related Terms: 3D Printing, Advanced Manufacturing, CNC Machining, Design for Additive Manufacturing (DfAM), Material Extrusion, Powder Bed Fusion (PBF), Vat Photopolymerization

Advanced Manufacturing

Advanced Manufacturing refers to the use of innovative manufacturing processes, digital technologies, advanced materials, and automation to improve product quality, production efficiency, and manufacturing capabilities. The term encompasses a wide range of technologies—including additive manufacturing, precision machining, robotics, automation, and digital manufacturing—that enable manufacturers to produce increasingly complex components with greater consistency and precision.

Related Terms: Additive Manufacturing, CAD, Digital Manufacturing

Anisotropy

Anisotropy is a material property in which mechanical characteristics vary depending on the direction of the applied load. In additive manufacturing, anisotropy commonly results from the layer-by-layer build process and differences in interlayer bonding.

Related Terms: FDM, Layer Thickness, Toolpath, Mechanical Properties

Annealing

Annealing is a heat treatment process that involves heating a material to a specified temperature and then cooling it under controlled conditions to alter its microstructure and properties. Depending on the material and application, annealing may be used to relieve residual stresses, improve dimensional stability, increase ductility, or enhance other mechanical properties. In additive manufacturing, annealing is commonly applied as a post-processing step for certain metal and polymer components.

Related Terms: Heat Treat, Hot Isostatic Pressing (HIP), Mechanical Properties, Post-Processing

B

BAAM (Big Area Additive Manufacturing)

Big Area Additive Manufacturing (BAAM) is a large-format material extrusion process that deposits thermoplastic composite materials at high rates to produce oversized parts and tooling. Similar to Fused Deposition Modeling (FDM), BAAM builds components layer by layer by extruding heated material through a nozzle. The process is commonly used to manufacture large molds, tooling, prototypes, and end-use components that exceed the practical build size of conventional additive manufacturing systems.

Related Terms: FDM, Material Extrusion, Feedstock

B-basis Allowables

B-Basis Allowables are statistically derived material property values that indicate at least 90% of a material population is expected to meet or exceed a specified mechanical property with 95% confidence. Widely used in aerospace certification and structural design, B-basis allowables provide engineers with conservative design values for critical components where material consistency and reliability are essential. These values are established through extensive material testing and statistical analysis in accordance with recognized industry standards.

Related Terms: NCAMP, Material Qualification, Mechanical Properties

Bed Adhesion

Bed Adhesion is the ability of the first layer of a printed part to remain securely attached to the build platform throughout the additive manufacturing process. Proper bed adhesion helps prevent part movement, warping, edge lifting, and print failure. Adhesion can be influenced by factors such as build platform preparation, material selection, process parameters, and the use of temporary features such as brims or rafts.

Related Terms: Build Platform, Brim, Raft, Warping

Binder Jetting

Binder Jetting is an additive manufacturing process that selectively deposits a liquid binding agent onto successive layers of powdered material to form a three-dimensional part. Once printing is complete, the unbound powder is removed and the part typically undergoes post-processing, such as curing, sintering, or infiltration, to achieve its final mechanical properties. Binder jetting is compatible with metal, ceramic, sand, and other powdered materials and is well suited for producing complex geometries without support structures.

Related Terms: Feedstock, Post-Processing, Sintering

Brim

Brim is a temporary printed feature that extends outward from the base of a part’s first layer to increase its contact area with the build platform. Brims improve bed adhesion and help reduce warping or edge lifting during printing, particularly for tall, narrow, or small-footprint parts. Unlike the part itself, the brim is removed after printing as part of post-processing.

Related Terms: Build Platform, FDM, Post-Processing, Raft

Build Chamber

Build Chamber is the enclosed area within an additive manufacturing system where a part is produced layer by layer. The build chamber provides a controlled environment that supports the printing process by maintaining process-specific conditions such as temperature, atmosphere, humidity, or inert gas composition, depending on the additive manufacturing technology. The size of the build chamber also defines the maximum dimensions of a part that can be manufactured in a single build.

Related Terms: Build Platform, Build Volume

Build Orientation

Build Orientation is the position and alignment of a part within an additive manufacturing system during production. Build orientation influences factors such as support structure requirements, surface finish, dimensional accuracy, mechanical properties, build time, and post-processing operations. Selecting an appropriate build orientation is an important aspect of design for additive manufacturing (DfAM), as it can affect manufacturing efficiency, material usage, and the overall performance of the finished component.

Related Terms: Design for Additive Manufacturing (DfAM), Layer Thickness, Overhang, Support Structures, Surface Finish, Warping

Build Platform

Build Platform is the surface within an additive manufacturing system on which a part is built layer by layer. Depending on the manufacturing process, the build platform may be heated, removable, or designed to support powder beds, photopolymer resins, or extruded materials. Proper preparation of the build platform is essential for part adhesion, dimensional accuracy, and successful printing.

Related Terms: Build Chamber, Build Volume, Brim, Raft

Build Plate

See Build Platform

Build Volume

Build Volume is the maximum three-dimensional space available for manufacturing a part within an additive manufacturing system. Build volume is typically defined by the machine’s maximum dimensions along the X, Y, and Z axes and determines the largest part—or arrangement of multiple parts—that can be produced in a single build. Parts that exceed the available build volume may require redesign, segmentation, or assembly after manufacturing.

Related Terms: Build Chamber, Build Platform

C

Class A Show Model

A Class A Show Model is a high-quality prototype or display model produced to accurately represent the appearance of a finished product. Unlike functional prototypes or production parts, Class A show models are typically created for product demonstrations, trade shows, architectural presentations, investor meetings, marketing photography, and other visual applications where surface finish, color, and cosmetic detail are the primary requirements.

Related Terms: Prototype, Surface Finish

Computer Aided Design (CAD)

Computer-Aided Design (CAD) is the use of computer software to create, modify, analyze, and document two-dimensional and three-dimensional digital models of parts, assemblies, and products. CAD models define the geometry and design intent of a component and serve as the primary source for manufacturing, engineering analysis, inspection, and product documentation. In additive manufacturing, CAD models are typically converted into printable file formats before production.

Related Terms: CAM, STL

Computer-Aided Manufacturing (CAM)

Computer-Aided Manufacturing (CAM) is the use of computer software to generate the instructions required to manufacture a part from a digital design. CAM software converts CAD models into machine-specific toolpaths or process instructions used to control manufacturing equipment such as CNC machines and certain additive manufacturing systems. By automating manufacturing planning, CAM helps improve accuracy, repeatability, and production efficiency.

Related Terms: CAD, Computer Numerical Control (CNC), Toolpath, Toolpath Optimization

Computed Tomography (CT) Scanning

Computed Tomography (CT) Scanning is a non-destructive inspection method that uses X-rays to generate a detailed three-dimensional representation of a manufactured part. By capturing and reconstructing hundreds or thousands of cross-sectional images, CT scanning enables inspectors to evaluate both external and internal features without cutting or damaging the component. In additive manufacturing, CT scanning is commonly used to verify internal geometries, identify defects such as porosity or voids, and support dimensional inspection and quality assurance for complex parts.

Related Terms: Coordinate Measuring Machine (CMM), Non-Destructive Testing (NDT), Porosity, Quality Assurance

Computer Numerical Control (CNC)

Computer Numerical Control (CNC) is a manufacturing method in which machine tools are controlled by computer-generated instructions to produce parts with high precision and repeatability. CNC technology automates machining operations such as milling, turning, drilling, and grinding by directing the movement of cutting tools and workpieces according to programmed toolpaths. CNC manufacturing is widely used to produce prototype and production components across aerospace, defense, medical, automotive, and other precision industries.

Related Terms: CAD, CAM, Toolpath

CNC Machining

CNC Machining is a subtractive manufacturing process that uses computer numerical control (CNC) machine tools to remove material from a workpiece and produce a finished part. Within additive manufacturing workflows, CNC machining is commonly used as a secondary operation to achieve tight dimensional tolerances, improve surface finishes, machine critical features, or prepare mating surfaces that cannot be produced to final specifications through additive manufacturing alone. The combination of additive manufacturing and CNC machining enables manufacturers to produce complex components while meeting demanding performance and quality requirements.

Related Terms: Computer Numerical Control (CNC), Post-Processing

Conformal Cooling

Conformal Cooling is a cooling strategy in which internal cooling channels are designed to closely follow the contours of a molded or manufactured part. Unlike conventional straight-drilled cooling channels, conformal cooling channels maintain a more consistent distance from the tool surface, improving heat transfer and temperature uniformity. Because these complex internal passages are often impossible or impractical to produce using conventional machining, conformal cooling is commonly enabled through metal additive manufacturing for applications such as injection molding tooling.

Related Terms: Additive Manufacturing, Tooling, Thermal Management

Controlled Unclassified Information (CUI)

Controlled Unclassified Information (CUI) is sensitive government information that requires safeguarding or dissemination controls but is not classified under national security standards. CUI may include technical data, engineering drawings, specifications, procurement information, and other controlled information shared with contractors performing work for the U.S. government. Organizations that handle CUI are required to implement applicable security controls to protect the information from unauthorized access or disclosure.

Related Terms: Cybersecurity Maturity Model Certification (CMMC), Federal Contract Information (FCI), ITAR

Coordinate Measuring Machine (CMM)

Coordinate Measuring Machine (CMM) is a precision inspection system used to measure the physical dimensions and geometry of manufactured parts. A CMM uses a tactile probe or non-contact sensor to collect measurements at defined points on a component, allowing inspectors to verify dimensions, geometric tolerances, and conformance to engineering drawings or CAD models. CMM inspection is widely used for quality assurance, first article inspection, and production verification across aerospace, medical, automotive, and other precision manufacturing industries.

Related Terms: CAD, First Article Inspection (FAI), Geometric Dimensioning and Tolerancing (GD&T), Quality Assurance

Coupon

See Test Coupon

Cybersecurity Maturity Model Certification (CMMC)

Cybersecurity Maturity Model Certification (CMMC) is a cybersecurity framework developed by the U.S. Department of Defense (DoD) to verify that organizations handling Federal Contract Information (FCI) and Controlled Unclassified Information (CUI) have implemented required cybersecurity practices and controls. CMMC establishes certification requirements for companies throughout the defense industrial base and is intended to help safeguard sensitive information shared across the defense supply chain.

Related Terms: Controlled Unclassified Information (CUI), Federal Contract Information (FCI), ITAR

D

Design for Additive Manufacturing (DfAM)

Design for Additive Manufacturing (DfAM) is an engineering approach that optimizes parts specifically for additive manufacturing processes. Rather than adapting designs intended for conventional manufacturing methods, DfAM considers the capabilities and constraints of additive manufacturing from the earliest stages of product development. This approach may incorporate features such as lightweight structures, part consolidation, internal channels, lattice geometries, and topology optimization to improve performance, manufacturability, or production efficiency.

Related Terms: Additive Manufacturing, Lattice Structure, Part Consolidation, Topology Optimization

Digital Manufacturing

Digital Manufacturing is the integration of digital technologies, data, and connected workflows throughout the manufacturing lifecycle. It combines tools such as computer-aided design (CAD), computer-aided manufacturing (CAM), simulation, automation, and production data to support the design, manufacture, inspection, and management of parts and products. In additive manufacturing, digital manufacturing enables greater process control, repeatability, traceability, and collaboration across the product lifecycle.

Related Terms: CAD, CAM, Digital Thread

Digital Thread

Digital Thread is a connected flow of digital information that links data generated throughout a product’s lifecycle, from design and manufacturing to inspection, testing, and sustainment. By connecting data across systems and processes, a digital thread provides traceability and enables stakeholders to access a consistent record of a product’s development and manufacturing history. In additive manufacturing, the digital thread may include CAD models, build files, machine parameters, inspection results, material certifications, and production records.

Related Terms: CAD, Digital Manufacturing

 

Digital Light Processing (DLP)

Digital Light Processing (DLP) is an additive manufacturing process that uses a digital light projector to selectively cure liquid photopolymer resin, producing parts layer by layer. Unlike laser-based vat photopolymerization systems, DLP cures an entire layer simultaneously by projecting a two-dimensional image onto the resin surface. The process is commonly used to produce components with fine feature resolution, smooth surface finishes, and high dimensional accuracy.

Related Terms: Photopolymer, Resin, Stereolithography (SLA), Vat Photopolymerization

E

Elastic Modulus

Elastic Modulus, also called Modulus of Elasticity or Young’s Modulus, is a measure of a material’s stiffness, describing its resistance to elastic deformation when subjected to a load. Materials with a higher elastic modulus deform less under the same applied stress, while materials with a lower elastic modulus deform more. Elastic modulus is a fundamental mechanical property used in engineering analysis and material selection.

Related Terms: Mechanical Properties, Tensile Testing, Yield Strength

EOS

EOS is a manufacturer of industrial additive manufacturing systems, materials, and software for polymer and metal additive manufacturing. The company is widely recognized for its laser powder bed fusion (LPBF) and polymer powder bed fusion technologies, and its equipment is used across aerospace, medical, industrial, and other advanced manufacturing industries.

Related Terms: Laser Powder Bed Fusion (LPBF)

F

Feedstock

Feedstock is the raw material used to produce a part through an additive manufacturing process. Depending on the technology, feedstock may be supplied as metal powder, polymer powder, thermoplastic filament, liquid photopolymer resin, wire, pellets, or other material forms. The characteristics of the feedstock—including particle size, chemistry, moisture content, and consistency—can significantly influence part quality, mechanical properties, and process repeatability.

Related Terms: Filament, Photopolymer, Powder Bed Fusion (PBF), Resin

Federal Acquisition Regulation (FAR)

The Federal Acquisition Regulation (FAR) is the primary set of rules governing how the U.S. federal government acquires products and services. Maintained jointly by the Department of Defense (DoD), General Services Administration (GSA), and National Aeronautics and Space Administration (NASA), the FAR establishes uniform policies and procedures for federal procurement. Contractors performing work for the U.S. government must comply with applicable FAR requirements, which may include provisions related to cybersecurity, quality assurance, reporting, and contract performance.

Related Terms: Federal Contract Information (FCI), Controlled Unclassified Information (CUI), Cybersecurity Maturity Model Certification (CMMC), ITAR

Federal Contract Information (FCI)

Federal Contract Information (FCI) is information that is provided by or generated for the U.S. federal government under a contract and is not intended for public release. While FCI does not meet the definition of Controlled Unclassified Information (CUI), it must still be protected from unauthorized access in accordance with applicable federal requirements. Organizations that handle FCI are required to implement basic cybersecurity safeguards, including those outlined in the Federal Acquisition Regulation (FAR) and Cybersecurity Maturity Model Certification (CMMC) framework.

Related Terms: Controlled Unclassified Information (CUI), Cybersecurity Maturity Model Certification (CMMC), FAR, ITAR

Filament

Filament is a continuous strand of thermoplastic material used as feedstock in filament-based additive manufacturing processes, including Fused Deposition Modeling (FDM) and Fused Filament Fabrication (FFF). During printing, the filament is fed into a heated extruder, where it is softened and deposited layer by layer to build the part. Filaments are available in a wide range of engineering and high-performance materials, each offering different mechanical, thermal, and chemical properties for specific applications.

Related Terms: Feedstock, Fused Deposition Modeling (FDM), Fused Filament Fabrication (FFF), Material Extrusion, Thermoplastic

Final Design

Final Design is the completed and approved version of a product or component that is ready for production. It incorporates all required engineering, performance, manufacturing, and quality requirements following the design, testing, and validation process. In additive manufacturing, a final design may include process-specific features such as support strategies, build orientation, tolerances, and post-processing requirements to ensure the part can be manufactured consistently and meets its intended performance.

Related Terms: Computer-Aided Design (CAD), Design for Additive Manufacturing (DfAM), Production Part, Prototype

First Article Inspection (FAI)

First Article Inspection (FAI) is a formal verification process used to confirm that a manufacturing process can consistently produce a part that meets all engineering, design, and specification requirements. Typically performed on the first production part or the first part produced following a significant manufacturing change, an FAI verifies dimensions, materials, processes, and other product characteristics against the engineering drawing and applicable specifications. In aerospace and other highly regulated industries, First Article Inspection is commonly performed in accordance with AS9102.

Related Terms: Coordinate Measuring Machine (CMM), Quality Assurance, Traceability

Fused Deposition Modeling (FDM)

Fused Deposition Modeling (FDM) is an additive manufacturing process in which thermoplastic filament is heated and extruded through a nozzle to build a part layer by layer. The material is deposited along a programmed toolpath, where it cools and solidifies to form the final geometry. FDM is widely used for prototyping, tooling, and production applications across a broad range of engineering thermoplastics.

Fused Deposition Modeling (FDM) is a trademark of Stratasys. The technically equivalent, non-proprietary term defined by ASTM International is Fused Filament Fabrication (FFF).

Related Terms: Fused Filament Fabrication (FFF), Material Extrusion, Thermoplastic, Toolpath

Fused Filament Fabrication (FFF)

Fused Filament Fabrication (FFF) is the ASTM International term for the additive manufacturing process commonly known as Fused Deposition Modeling (FDM). See Fused Deposition Modeling (FDM)

G

G-code

G-code is a programming language used to control the motion and operation of computer numerical control (CNC) machines and many additive manufacturing systems. A G-code program consists of machine instructions that define movements, speeds, toolpaths, temperatures, and other process parameters required to manufacture a part. While the specific commands vary by machine and controller, G-code enables automated, repeatable production by translating digital manufacturing data into machine-readable instructions.

Related Terms: Computer-Aided Manufacturing (CAM), Computer Numerical Control (CNC), Toolpath, Toolpath Optimization

Generative Design

Generative Design is a computational design approach that uses software algorithms to automatically generate and evaluate multiple design solutions based on defined engineering requirements and constraints. Designers specify parameters such as loads, materials, manufacturing processes, performance objectives, and geometric constraints, while the software produces a range of potential designs for evaluation. Generative design is commonly used to explore lightweight, high-performance geometries and is often combined with additive manufacturing to produce components that would be difficult or impractical to manufacture using traditional methods.

Related Terms: Computer-Aided Design (CAD), Design for Additive Manufacturing (DfAM), Topology Optimization

Geometric Dimensioning and Tolerancing (GD&T)

Geometric Dimensioning and Tolerancing (GD&T) is a standardized engineering language used on technical drawings to define the allowable variation in the size, form, orientation, location, and profile of part features. Rather than relying solely on traditional dimensional tolerances, GD&T uses internationally recognized symbols to clearly communicate design intent and functional requirements. GD&T helps ensure that parts are manufactured, inspected, and assembled consistently, particularly for complex components requiring precise fit, function, and interchangeability.

Related Terms: Computer-Aided Design (CAD), Coordinate Measuring Machine (CMM), First Article Inspection (FAI), Tolerance

H

Heated Bed

A heated bed is a temperature-controlled build surface used in many material extrusion additive manufacturing systems, including Fused Deposition Modeling (FDM) and Fused Filament Fabrication (FFF). By maintaining a controlled temperature during printing, the heated bed helps improve first-layer adhesion, reduce thermal stresses, and minimize issues such as warping or part detachment. The optimal bed temperature varies depending on the filament material and printing process.

Related Terms: Bed Adhesion, Build Platform, Filament, Fused Deposition Modeling (FDM), Thermoplastic

Heat Treat

Heat Treat is a controlled thermal process used to alter the microstructure and mechanical properties of a metal without changing its shape. Depending on the material and treatment method, heat treating can improve strength, hardness, toughness, ductility, wear resistance, or relieve residual stresses introduced during manufacturing. In additive manufacturing, heat treatment is commonly performed after printing to achieve specified material properties or prepare parts for subsequent machining and finishing operations.

Related Terms: Annealing, Hot Isostatic Pressing (HIP), Post-Processing

HexPEKK®

HexPEKK® is ADDMAN’s proprietary carbon fiber-reinforced polyetherketoneketone (PEKK) material developed for additive manufacturing of high-performance aerospace and defense components. Manufactured using Selective Laser Sintering (SLS), HexPEKK combines the high-temperature performance and chemical resistance of PEKK with the enhanced stiffness of carbon fiber reinforcement. The material has undergone independent qualification through the National Center for Advanced Materials Performance (NCAMP) and is supported by published B-basis design allowables for use in engineering and certification activities.

Related Terms: B-Basis Allowables,  National Center for Advanced Materials Performance (NCAMP), Selective Laser Sintering (SLS)

Hot Isostatic Pressing (HIP)

Hot Isostatic Pressing (HIP) is a post-processing technique that uses high temperature and isostatic gas pressure to reduce internal porosity and improve the density and mechanical properties of metal components. In metal additive manufacturing, HIP is commonly used to enhance material performance and increase the structural integrity of critical parts for aerospace, defense, medical, and other demanding applications.

Related Terms: Heat Treat, Laser Powder Bed Fusion (LPBF), Mechanical Properties, Porosity, Post-Processing

HP

HP Inc. is a manufacturer of industrial additive manufacturing systems and the developer of Multi Jet Fusion (MJF) technology. HP’s industrial 3D printers are widely used to produce functional polymer prototypes, tooling, and end-use production parts. MJF systems use polymer powder feedstock and a combination of fusing and detailing agents to produce parts with high accuracy, consistent mechanical properties, and production-level repeatability.

Related Terms: Multi Jet Fusion (MJF)

I

International Traffic in Arms Regulations (ITAR)

The International Traffic in Arms Regulations (ITAR) are U.S. government regulations that control the export, import, and temporary transfer of defense-related articles, services, and technical data. Administered by the U.S. Department of State, ITAR is intended to protect U.S. national security by restricting access to controlled defense technologies. Manufacturers that produce ITAR-controlled products or handle ITAR-controlled technical data must comply with applicable regulatory requirements, including safeguards governing access, storage, and the sharing of controlled information.

Related Terms: Controlled Unclassified Information (CUI), Cybersecurity Maturity Model Certification (CMMC), Federal Acquisition Regulation (FAR), Federal Contract Information (FCI)

 

Infill

Infill is the internal structure printed inside a part to provide strength and support while reducing material usage, weight, and build time. In material extrusion processes such as Fused Deposition Modeling (FDM), infill is generated as a repeating geometric pattern enclosed by the part’s outer walls. The density and pattern of the infill can be adjusted to achieve the desired balance of mechanical performance, material consumption, and print efficiency based on the application’s requirements.

Related Terms: Fused Deposition Modeling (FDM), Material Extrusion, Toolpath

Initial Design

Initial Design is the first engineering representation of a product or component developed to satisfy functional, performance, and manufacturing objectives. It establishes the overall concept, geometry, and design intent, serving as the foundation for subsequent analysis, prototyping, testing, and refinement. In additive manufacturing, an initial design may undergo multiple iterations to optimize performance, manufacturability, and cost before reaching the final approved design for production.

Related Terms: Computer-Aided Design (CAD), Design for Additive Manufacturing (DfAM), Final Design, Prototype

L

Laser Powder Bed Fusion (LPBF)

Laser Powder Bed Fusion (LPBF) is an additive manufacturing process in which a high-powered laser selectively melts and fuses regions of a thin layer of metal powder to build a part one layer at a time. After each layer is completed, a recoater spreads a new layer of powder across the build platform, and the process repeats until the part is complete. LPBF is used to manufacture complex metal components with high precision and is compatible with a wide range of engineering alloys, including titanium, aluminum, stainless steels, nickel-based superalloys, cobalt chrome, and refractory metals.

Related Terms: Build Platform, Laser, Metal Additive Manufacturing, Powder Bed Fusion, Recoater

Lattice Structure

A Lattice Structure is an engineered network of interconnected cells or repeating geometric features designed to achieve specific mechanical, thermal, or functional performance characteristics while minimizing weight. Unlike slicer-generated infill, lattice structures are intentionally incorporated into the part’s design and may be optimized for properties such as stiffness, energy absorption, heat transfer, or fluid flow. Lattice structures are commonly used in additive manufacturing because they can produce complex internal geometries that are difficult or impossible to manufacture using traditional methods.

Related Terms: Design for Additive Manufacturing (DfAM), Infill, Topology Optimization

Layer Thickness

Layer Thickness is the height of each individual layer deposited or solidified during an additive manufacturing process. It is one of the primary process parameters influencing surface finish, dimensional accuracy, feature resolution, build time, and mechanical properties. Thinner layers can improve the reproduction of fine details and reduce the appearance of layer lines, while thicker layers generally shorten build times. The optimal layer thickness depends on the additive manufacturing process, material, and application requirements.

Related Terms: Build Orientation, Resolution, Surface Finish

M

Material Database

A Material Database is a centralized collection of material property data used by engineers to support material selection, product design, manufacturing, and analysis. Depending on the application, a material database may include mechanical, thermal, electrical, chemical, and physical properties, as well as processing parameters, qualification data, and design allowables. In additive manufacturing, material databases often provide information needed to evaluate material performance, compare material options, and support engineering and certification activities.

Related Terms: B-Basis Allowables, Feedstock, Material Qualification, Material Properties

Material Extrusion

Material Extrusion is an additive manufacturing process in which material is selectively dispensed through a nozzle or orifice to build a part layer by layer. The process most commonly uses thermoplastic filament, which is heated and extruded to form each successive layer. Material Extrusion is the ASTM/ISO classification for this family of additive manufacturing technologies and includes processes such as Fused Deposition Modeling (FDM) and Fused Filament Fabrication (FFF).

Related Terms: Feedstock, Filament, Fused Deposition Modeling (FDM), Fused Filament Fabrication (FFF), Toolpath

Material Properties

Material Properties are the measurable characteristics of a material that determine how it behaves under specific conditions and influence its suitability for a given application. Material properties may include mechanical, thermal, electrical, chemical, physical, and optical characteristics. Engineers use material property data to compare materials, predict performance, support design decisions, and verify that components will meet functional and environmental requirements.

Related Terms: Material Database, Material Qualification, Mechanical Properties, Mechanical Testing

Material Qualification

Material Qualification is the process of demonstrating, through testing and analysis, that a material consistently meets specified performance and quality requirements for its intended application. Qualification typically includes evaluating mechanical, physical, thermal, and chemical properties using standardized test methods and documented procedures. In additive manufacturing, material qualification helps establish confidence that a material and manufacturing process can repeatedly produce parts that satisfy engineering, regulatory, and certification requirements.

Related Terms: B-Basis Allowables, Material Database, Mechanical Testing, Quality Assurance (QA), Test Coupon

Mechanical Properties

Mechanical Properties are the characteristics that describe how a material responds to applied forces or loads. Common mechanical properties include tensile strength, yield strength, stiffness, hardness, ductility, fatigue resistance, fracture toughness, and elongation. These properties are determined through standardized mechanical testing and are used by engineers to evaluate material performance, compare material options, and ensure components meet design and application requirements.

Related Terms: Material Qualification, Mechanical Testing, Tensile Testing, Test Coupon

Mechanical Testing

Mechanical Testing is the process of evaluating a material’s or component’s response to applied forces to determine its mechanical properties and performance. Common tests measure characteristics such as tensile strength, compressive strength, fatigue resistance, hardness, impact resistance, and elongation. In additive manufacturing, mechanical testing is used to characterize material performance, validate manufacturing processes, verify compliance with engineering requirements, and support material qualification and certification activities.

Related Terms: B-Basis Allowables, Material Qualification, Quality Assurance (QA), Tensile Testing, Test Coupon

Mesh

A Mesh is a digital representation of a three-dimensional object composed of interconnected polygons, most commonly triangles, that define the part’s surface geometry. Mesh models are widely used in additive manufacturing because they provide the geometric information needed by slicing software to generate printable layers and toolpaths. Common mesh file formats include STL and 3MF. Before printing, a mesh may require inspection or repair to correct geometry errors that could affect the manufacturing process.

Related Terms: Computer-Aided Design (CAD), Mesh Repair, Slicing, STL

Mesh Repair

Mesh Repair is the process of identifying and correcting errors in a three-dimensional digital model to prepare it for additive manufacturing. Common repairs include closing holes, removing self-intersections, correcting inverted surface normals, eliminating non-manifold geometry, and ensuring the model forms a watertight mesh. Mesh repair helps ensure that slicing software can accurately generate toolpaths and reduces the risk of build errors or failed prints.

Related Terms: Computer-Aided Design (CAD), Mesh, Slicing, STL

Multi Jet Fusion (MJF)

Multi Jet Fusion (MJF) is a polymer additive manufacturing process developed by HP that builds parts by selectively applying fusing and detailing agents to a thin layer of polymer powder before passing an infrared energy source over the build area. The process repeats layer by layer until the part is complete. MJF is widely used for producing functional prototypes, end-use components, and production parts with fine feature detail, consistent mechanical properties, and high dimensional accuracy.

Related Terms: Build Chamber, Build Platform, HP, Powder Bed Fusion

N

National Center for Advanced Materials Performance (NCAMP)

The National Center for Advanced Materials Performance (NCAMP) is an industry program administered by the National Institute for Aviation Research (NIAR) at Wichita State University that generates standardized material qualification data for aerospace applications. NCAMP develops material property datasets using rigorous testing and statistical analysis to support the certification and use of advanced materials in aircraft and other regulated industries. These independently generated data help reduce redundant material qualification efforts and provide engineers with trusted information for design and certification activities.

Related Terms: B-Basis Allowables, HexPEKK®, Material Database, Material Qualification, Mechanical Testing

NADCAP

NADCAP (National Aerospace and Defense Contractors Accreditation Program) is an industry-managed accreditation program that establishes standardized requirements for special manufacturing processes used in the aerospace and defense industries. Administered by the Performance Review Institute (PRI), NADCAP accreditation demonstrates that a manufacturer has successfully completed a rigorous audit verifying compliance with industry-recognized process requirements. The program covers a wide range of special processes, including heat treating, non-destructive testing, welding, coatings, and chemical processing.

Related Terms: AS9100, Heat Treat, Non-Destructive Testing (NDT), Quality Assurance (QA)

Near Net Shape

Near Net Shape describes a manufacturing approach in which a part is produced close to its final geometry, requiring only minimal machining or finishing operations to achieve the specified dimensions, tolerances, or surface finish. Additive manufacturing is often used as a near net shape process because it can produce complex geometries with little material waste while reducing the amount of secondary machining needed. Near net shape manufacturing can improve material utilization, reduce production time, and simplify the manufacturing process for many applications.

Related Terms: CNC Machining, Laser Powder Bed Fusion (LPBF), Post-Processing, Support Structures

Non-Destructive Testing (NDT)

Non-Destructive Testing (NDT) is a group of inspection methods used to evaluate the integrity, quality, or characteristics of a material or component without causing damage or affecting its intended use. Common NDT methods include computed tomography (CT) scanning, ultrasonic testing, radiographic testing, liquid penetrant inspection, magnetic particle inspection, and eddy current testing. In additive manufacturing, NDT is used to detect internal and surface defects, verify part quality, and support qualification and production inspection requirements.

Related Terms: Computed Tomography (CT) Scanning, Mechanical Testing, Quality Assurance (QA), Test Coupon

NURBS (Non-Uniform Rational B-Splines)

NURBS (Non-Uniform Rational B-Splines) is a mathematical method used in computer-aided design (CAD) to represent curves and surfaces with a high degree of accuracy and precision. Unlike mesh models, which approximate geometry using polygons, NURBS models define smooth surfaces mathematically, making them well suited for engineering design, manufacturing, and product development. Most CAD systems use NURBS geometry as the basis for creating and modifying solid models before they are converted to mesh formats for additive manufacturing.

Related Terms: Computer-Aided Design (CAD), Mesh, Mesh Repair, STL

O

Overhang

An Overhang is a portion of a part that extends outward beyond the material or previously built layers beneath it during the additive manufacturing process. Depending on the manufacturing technology, material, and overhang angle, these features may require support structures to prevent distortion, sagging, or build failure. Designing overhangs appropriately and selecting an optimal build orientation are important considerations for improving manufacturability and reducing post-processing requirements.

Related Terms: Build Orientation, Design for Additive Manufacturing (DfAM), Support Structures

P

Part Consolidation

Part Consolidation is the process of combining multiple individual components into a single manufactured part. In additive manufacturing, part consolidation is often achieved by producing complex geometries that would otherwise require multiple machined, cast, or assembled components. Consolidating parts can reduce assembly operations, eliminate fasteners or welds, simplify supply chains, and improve reliability by reducing the number of individual components within an assembly.

Related Terms: Additive Manufacturing, CNC Machining, Design for Additive Manufacturing (DfAM), Prototype

Part Qualification

Part Qualification is the process of verifying that a manufactured component meets all specified design, performance, quality, and regulatory requirements for its intended application. Qualification may include dimensional inspection, mechanical testing, non-destructive testing, environmental testing, functional evaluation, and documentation review, depending on the application. In additive manufacturing, part qualification helps demonstrate that a component can be manufactured consistently and performs as required throughout its intended service life.

Related Terms: First Article Inspection (FAI), Material Qualification, Mechanical Testing, Non-Destructive Testing (NDT), Quality Assurance (QA)

Photopolymer

A Photopolymer is a light-sensitive polymer that undergoes a chemical reaction and solidifies when exposed to a specific wavelength of light, typically ultraviolet (UV) light. In additive manufacturing, photopolymers are used as liquid feedstocks in processes such as Stereolithography (SLA), Digital Light Processing (DLP), and PolyJet. Photopolymer formulations are available with a wide range of mechanical, thermal, optical, and biocompatible properties to support diverse prototyping and production applications.

Related Terms: Digital Light Processing (DLP), PolyJet, Resin, Stereolithography (SLA), Ultraviolet (UV) Curing

PolyJet

PolyJet is a proprietary additive manufacturing technology developed by Stratasys that produces parts by jetting microscopic droplets of liquid photopolymer onto a build platform and curing them with ultraviolet (UV) light. The process enables the production of highly detailed parts with smooth surface finishes, fine feature resolution, and the ability to combine multiple materials or material properties within a single build, depending on the system configuration. PolyJet is commonly used for concept models, functional prototypes, medical models, and applications requiring exceptional dimensional accuracy and surface quality.

Related Terms: Photopolymer, Resin, Stratasys, Ultraviolet (UV) Curing

Porosity

Porosity is the presence of voids or small pockets of empty space within a material or manufactured component. In additive manufacturing, porosity can result from factors such as process parameters, material quality, or manufacturing conditions and may affect mechanical properties, density, fatigue performance, and pressure-tightness. Depending on the application, porosity may be evaluated through mechanical testing, computed tomography (CT) scanning, or other inspection methods as part of quality assurance and qualification activities.

Related Terms: Computed Tomography (CT) Scanning, Laser Powder Bed Fusion (LPBF), Mechanical Testing, Non-Destructive Testing (NDT), Quality Assurance (QA)

Post-Processing

Post-Processing refers to the manufacturing operations performed after a part has been produced to achieve its final dimensions, material properties, surface finish, or functional requirements. Depending on the manufacturing process and application, post-processing may include support removal, heat treatment, machining, surface finishing, inspection, coating, assembly, or other secondary operations. In additive manufacturing, post-processing is often an essential step in preparing printed parts for production use.

Related Terms: CNC Machining, Heat Treat, Near Net Shape, Non-Destructive Testing (NDT), Support Structures

Powder Bed Fusion

Powder Bed Fusion (PBF) is a family of additive manufacturing processes in which thermal energy selectively fuses regions of a powdered material to build parts layer by layer. After each layer is fused, a new layer of powder is spread across the build area, and the process repeats until the part is complete. Depending on the process, the energy source may be a laser or another heat source, and materials may include metals or polymers. Powder bed fusion encompasses several additive manufacturing technologies, including Laser Powder Bed Fusion (LPBF), Selective Laser Sintering (SLS), and Multi Jet Fusion (MJF).

Related Terms: Additive Manufacturing, Build Platform, Laser Powder Bed Fusion (LPBF), Multi Jet Fusion (MJF), Powder, Selective Laser Sintering (SLS)

Printhead

A Printhead is a machine component that precisely deposits or dispenses material, binding agents, or processing agents during an additive manufacturing build. Depending on the manufacturing technology, a printhead may jet liquid photopolymers, fusing and detailing agents, or binder materials onto the build surface or powder bed. The accuracy and performance of the printhead play an important role in part quality, feature resolution, and repeatability.

Related Terms: Binder Jetting, Multi Jet Fusion (MJF), PolyJet, Repeatability

Print Parameter

A Print Parameter is a machine setting or process variable that influences how a part is manufactured during an additive manufacturing build. Print parameters may include factors such as layer thickness, laser power, scan speed, build temperature, extrusion temperature, or print speed, depending on the manufacturing process. Carefully controlled print parameters help ensure consistent part quality, dimensional accuracy, mechanical properties, and repeatable manufacturing results.

Related Terms: Layer Thickness, Laser Powder Bed Fusion (LPBF), Material Qualification, Process Qualification, Repeatability

Process Qualification

Process Qualification is the process of demonstrating that a manufacturing process can consistently produce parts that meet specified quality, performance, and regulatory requirements. Qualification typically involves establishing and validating process parameters, equipment performance, inspection methods, and documented procedures to ensure repeatable manufacturing results. In additive manufacturing, process qualification helps verify that the combination of machine, material, software, and operating parameters can reliably produce conforming parts.

Related Terms: Material Qualification, Part Qualification, Quality Assurance (QA), Repeatability, Validation

Production Part

A Production Part is a component manufactured for its intended end-use application in accordance with approved design specifications, quality requirements, and manufacturing processes. Unlike a prototype, a production part is produced using qualified materials and controlled manufacturing processes to meet established performance, reliability, and regulatory requirements. Production parts may be manufactured in low, medium, or high volumes depending on the application and production needs.

Related Terms: Final Design, Material Qualification, Part Qualification, Process Qualification, Prototype

Prototype

A Prototype is an early physical representation of a product or component produced to evaluate its design, fit, form, function, or manufacturability before full-scale production. Prototypes may be used to identify design improvements, verify performance, gather user feedback, or validate manufacturing approaches. Additive manufacturing is widely used for prototyping because it enables rapid design iteration and the production of complex geometries without the need for production tooling.

Related Terms: Computer-Aided Design (CAD), Design for Additive Manufacturing (DfAM), Final Design, Initial Design, Production Part

Q

Qualification

Qualification is the documented process of demonstrating that a material, manufacturing process, or finished part consistently meets specified performance, quality, and regulatory requirements for its intended application. Qualification typically involves testing, inspection, analysis, and the review of objective evidence to verify compliance with defined acceptance criteria. In additive manufacturing, qualification provides confidence that materials, processes, and components can be produced repeatedly and perform as intended in service.

Related Terms: Material Qualification, Mechanical Testing, Part Qualification, Process Qualification, Validation

Quality Assurance (QA)

Quality Assurance (QA) is the systematic process of establishing and maintaining procedures, standards, and controls to ensure that products consistently meet specified quality, performance, and regulatory requirements. Quality assurance encompasses activities such as process control, documentation, inspection, testing, corrective actions, and continuous improvement throughout the manufacturing lifecycle. In additive manufacturing, QA helps ensure repeatable production, traceability, and compliance with customer and industry requirements.

Related Terms: First Article Inspection (FAI), Mechanical Testing, Non-Destructive Testing (NDT), Qualification, Traceability

Quality Management System (QMS)

A Quality Management System (QMS) is a formal framework of policies, processes, procedures, and documented responsibilities used to consistently meet customer, regulatory, and quality requirements. A QMS establishes standardized methods for managing manufacturing operations, controlling documentation, monitoring performance, addressing nonconformities, and driving continual improvement. In manufacturing, quality management systems are commonly based on recognized standards such as ISO 9001 and AS9100.

Related Terms: AS9100, ISO 9001, Quality Assurance (QA), Qualification, Traceability

R

Raft

A Raft is a sacrificial base layer printed beneath a part during material extrusion processes such as Fused Deposition Modeling (FDM) to improve bed adhesion and provide a stable foundation for the build. After printing is complete, the raft is removed as part of post-processing. Rafts are commonly used to reduce the risk of warping, improve first-layer stability, and support parts with limited contact area on the build platform.

Related Terms: Bed Adhesion, Brim, Build Platform, Fused Deposition Modeling (FDM), Heated Bed

Recoater

A Recoater is a machine component that spreads a thin, uniform layer of powder across the build platform during powder bed additive manufacturing processes. After each layer is fused, the recoater applies a fresh layer of powder to prepare the build surface for the next layer. Consistent powder distribution by the recoater is critical for achieving uniform layer thickness, dimensional accuracy, repeatable part quality, and reliable manufacturing performance.

Related Terms: Build Platform, Laser Powder Bed Fusion (LPBF), Layer Thickness, Powder Bed Fusion, Selective Laser Sintering (SLS)

Refractory Metal

A Refractory Metal is a class of metals characterized by exceptionally high melting points and the ability to maintain strength and stability at elevated temperatures. Common refractory metals include tungsten, molybdenum, tantalum, niobium, and their alloys. Because of their high-temperature performance and resistance to thermal degradation, refractory metals are widely used in aerospace, defense, space propulsion, and other demanding applications.

Related Terms: Mechanical Properties, Superalloy

Repeatability

Repeatability is the ability of a manufacturing process to consistently produce parts that meet the same specified requirements over multiple production cycles. A repeatable process delivers consistent dimensional accuracy, mechanical properties, and quality when using the same equipment, materials, process parameters, and operating conditions. Repeatability is a key indicator of process stability and is essential for production manufacturing and part qualification.

Related Terms: Part Qualification, Print Parameter, Process Qualification, Production Part, Quality Assurance (QA)

Resin

Resin is a liquid photopolymer material used as feedstock in additive manufacturing processes such as Stereolithography (SLA), Digital Light Processing (DLP), Material Jetting, and Vat Photopolymerization. During printing, the resin is selectively cured by ultraviolet (UV) light to form solid layers that build the final part. Resins are available in a wide range of formulations designed to achieve specific mechanical, thermal, optical, and biocompatibility requirements.

Related Terms: Digital Light Processing (DLP), Feedstock, Photopolymer, Stereolithography (SLA), Vat Photopolymerization

Resolution

Resolution is the ability of an additive manufacturing process to accurately reproduce fine details and small features in a printed part. Resolution is influenced by factors such as layer thickness, laser or nozzle size, printhead accuracy, material properties, and process parameters. Higher resolution enables the production of finer features, sharper edges, and more detailed geometries, although achievable resolution varies by additive manufacturing technology and application.

Related Terms: Layer Thickness, Print Parameter, Printhead, Surface Finish

S

Selective Laser Sintering (SLS)

Selective Laser Sintering (SLS) is an additive manufacturing process in which a laser selectively fuses polymer powder to build a part one layer at a time. After each layer is completed, a recoater spreads a new layer of powder across the build platform, and the process repeats until the part is complete. The surrounding unsintered powder supports the part during the build, allowing complex geometries to be produced with little or no dedicated support structures. SLS is widely used for functional prototypes, end-use components, and production applications.

Related Terms: Build Platform, Laser, Powder Bed Fusion, Recoater

Sintering

Sintering is a manufacturing process in which powdered material is heated to a temperature below its melting point, causing individual particles to bond together and form a solid structure. Sintering is used in a variety of manufacturing processes, including powder metallurgy, ceramics, and additive manufacturing. In polymer additive manufacturing, selective laser sintering (SLS) uses a laser to selectively fuse powder into a solid part one layer at a time.

Related Terms: Laser, Powder Bed Fusion, Selective Laser Sintering (SLS)

Slicing

Slicing is the process of converting a three-dimensional digital model into a series of two-dimensional layers and machine instructions that an additive manufacturing system can interpret and execute. During slicing, software determines the part’s layer structure and generates build information such as toolpaths, print parameters, support structures, and other process-specific instructions. The resulting build file is then used to manufacture the part.

Related Terms: Mesh, Mesh Repair, Print Parameter, STL File, Support Structures

Stratasys

Stratasys is a manufacturer of industrial additive manufacturing systems and materials. The company developed Fused Deposition Modeling (FDM) and PolyJet, two widely used additive manufacturing technologies for producing prototypes, tooling, and end-use components across industries including aerospace, medical, automotive, and consumer products.

Related Terms: Fused Deposition Modeling (FDM), PolyJet

Stereolithography (SLA)

Stereolithography (SLA) is an additive manufacturing process in which a laser selectively cures liquid photopolymer resin to build a part one layer at a time. After each layer is cured, the build platform moves to allow fresh resin to cover the build area, and the process repeats until the part is complete. SLA is widely used to produce parts with fine feature detail, smooth surface finishes, and high dimensional accuracy for prototyping, tooling, and end-use applications.

Related Terms: Digital Light Processing (DLP), Photopolymer, Resin, Ultraviolet (UV) Curing, Vat Photopolymerization

STL File

An STL File is a digital file format commonly used in additive manufacturing to represent the surface geometry of a three-dimensional object as a mesh of interconnected triangles. Unlike native CAD files, an STL file contains only geometric information and does not retain design features, material properties, colors, or manufacturing metadata. STL files are widely used as input for slicing software, which converts the model into machine instructions for additive manufacturing.

Related Terms: Computer-Aided Design (CAD), Mesh, Mesh Repair, NURBS, Slicing

Superalloy

A Superalloy is a class of high-performance alloys engineered to maintain strength, corrosion resistance, and mechanical properties at elevated temperatures. Superalloys are typically based on nickel, cobalt, or iron and are designed for demanding applications where conventional alloys may lose strength or deform under heat and stress. They are widely used in aerospace, defense, power generation, and other industries requiring exceptional high-temperature performance.

Related Terms: Mechanical Properties, Refractory Metal

Support Structures

Support Structures are temporary features generated or designed to provide stability for overhangs, bridges, or other unsupported geometries during the additive manufacturing process. Depending on the manufacturing technology, support structures may help anchor the part to the build platform, reduce distortion, improve heat transfer, or prevent build failure. After manufacturing is complete, support structures are typically removed during post-processing.

Related Terms: Build Orientation, Overhang, Post-Processing, Slicing

Surface Finish

Surface Finish is the texture, smoothness, and overall condition of a manufactured part’s surface after production and any required post-processing. Surface finish is influenced by factors such as the additive manufacturing process, layer thickness, build orientation, material, and post-processing operations. Depending on the application, surface finish may affect part appearance, dimensional accuracy, wear resistance, fatigue performance, friction, or the ability to receive coatings or secondary finishing processes.

Related Terms: Build Orientation, Layer Thickness, Post-Processing, Resolution

T

Tensile Strength

Tensile Strength is the maximum tensile stress a material can withstand before fracturing when subjected to a pulling force. It is determined through standardized mechanical testing and is commonly reported in units of pressure, such as pounds per square inch (psi) or megapascals (MPa). Tensile strength is one of the primary mechanical properties used to evaluate and compare engineering materials for structural and load-bearing applications.

Related Terms: Elastic Modulus, Material Properties, Mechanical Properties, Mechanical Testing, Tensile Testing, Yield Strength

Tensile Testing

Tensile Testing is a mechanical test used to evaluate how a material or manufactured part responds to forces that pull it apart. During the test, a standardized specimen is subjected to a controlled tensile load until it deforms or fractures. The results are used to determine mechanical properties such as tensile strength, yield strength, elongation, and elastic modulus.

Related Terms: Mechanical Properties, Mechanical Testing, Test Coupon, Yield Strength

Test Coupon

Test Coupon is a standardized specimen manufactured alongside or from the same material and process as a production part to evaluate material properties, process consistency, or manufacturing quality. Test coupons are commonly used for mechanical testing, metallurgical evaluation, dimensional verification, and process qualification. In additive manufacturing, coupons may be built within the same build as production components to help verify that the manufacturing process met specified requirements.

Related Terms: Material Qualification, Mechanical Properties, Process Qualification, Quality Assurance

Thermal Management

Thermal Management is the control of heat generation, transfer, and dissipation within a component or system to maintain safe and reliable operating temperatures. Effective thermal management helps ensure performance, efficiency, and service life by preventing excessive temperatures that can degrade materials or impair functionality. In additive manufacturing, thermal management features such as conformal cooling channels, heat exchangers, and optimized internal geometries can be produced to improve heat transfer and cooling performance.

Related Terms: Conformal Cooling, Topology Optimization

Thermoplastic

Thermoplastic is a class of polymer materials that soften when heated and solidify when cooled without undergoing a permanent chemical change. This reversible behavior allows thermoplastics to be processed multiple times using manufacturing methods such as additive manufacturing, injection molding, and extrusion. Thermoplastics are widely used in engineering applications because they are available in a broad range of mechanical, thermal, and chemical performance characteristics.

Related Terms: Additive Manufacturing, Material Extrusion

Tolerance

Tolerance is the allowable variation in a part’s dimensions, geometry, or other specified characteristics while still meeting design requirements. Tolerances define the acceptable range between the minimum and maximum permissible values for a feature, helping ensure that manufactured parts fit, function, and perform as intended. The achievable tolerance depends on factors such as the manufacturing process, material, part geometry, and post-processing operations.

Related Terms: Computer Numerical Control (CNC), GD&T, Part Qualification, Quality Assurance (QA), Surface Finish

Toolpath

A Toolpath is the programmed path that a manufacturing machine follows to produce a part. In additive manufacturing, a toolpath defines how material is deposited, fused, or cured during the build process. In CNC machining, a toolpath specifies the movement of cutting tools to remove material and achieve the desired geometry. Toolpaths are generated by computer software based on the digital part model and manufacturing process requirements.

Related Terms: Computer-Aided Manufacturing (CAM), Computer Numerical Control (CNC), G-code, Print Parameter, Slicing

Tooling

Tooling refers to the specialized tools, fixtures, molds, dies, jigs, and other equipment used to manufacture, inspect, or assemble parts. Depending on the manufacturing process, tooling may include injection molds, machining fixtures, cutting tools, inspection gauges, or production aids. In additive manufacturing, tooling can also be produced using three-dimensional printing to accelerate development, reduce costs, or support low-volume production.

Related Terms: Additive Manufacturing, CNC Machining, Prototype

Toolpath Optimization

Toolpath Optimization is the process of improving the path followed by a manufacturing system during part production to increase efficiency, accuracy, or part quality. In additive manufacturing, toolpath optimization may involve adjusting scan strategies, deposition paths, or build sequences to improve surface finish, reduce build time, minimize residual stresses, or enhance mechanical performance. In subtractive manufacturing, toolpath optimization focuses on improving machining efficiency, cutting performance, and dimensional accuracy while reducing cycle time and tool wear.

Related Terms: Additive Manufacturing, CNC Machining, Design for Additive Manufacturing (DfAM), Surface Finish

Topology Optimization

Topology Optimization is a computational design method that determines the most efficient distribution of material within a defined design space while meeting specified performance requirements, such as strength, stiffness, or weight. Engineers define constraints, loads, and objectives, and optimization software removes unnecessary material to produce an optimized geometry. The resulting designs often feature organic shapes that are well suited for additive manufacturing.

Related Terms: Computer-Aided Design (CAD), Design for Additive Manufacturing (DfAM), Generative Design, Lattice Structure

Traceability

Traceability is the ability to identify and document the history, origin, processing, and movement of a material, component, or finished part throughout the manufacturing lifecycle. Traceability enables manufacturers to link products to records such as material certifications, manufacturing processes, inspection results, and quality documentation, supporting compliance, quality assurance, and product accountability.

Related Terms: Material Qualification, Part Qualification, Quality Assurance (QA), Quality Management System (QMS)

U

Ultraviolet (UV) Curing

Ultraviolet (UV) Curing is the process of using ultraviolet light to harden or solidify a photopolymer through a chemical reaction. In additive manufacturing, ultraviolet curing is used in vat photopolymerization and material jetting processes to selectively cure liquid resin into solid layers during part production. Additional ultraviolet curing may be performed after printing to improve the material’s mechanical properties and ensure the part reaches its intended performance characteristics.

Related Terms: Material Jetting, Photopolymer, PolyJet, Resin, Stereolithography (SLA), Vat Photopolymerization

V

Validation

Validation is the documented process of demonstrating that a manufacturing process, system, or method consistently produces results that meet predetermined requirements for its intended use. Validation typically involves collecting objective evidence through testing, analysis, and repeatable production to confirm that the process performs reliably under defined operating conditions. In regulated industries, validation is an essential component of quality management and supports consistent product quality and manufacturing control.

Related Terms: Material Qualification, Part Qualification, Process Qualification, Quality Assurance (QA), Quality Management System (QMS)

Vat Photopolymerization

Vat Photopolymerization is an additive manufacturing process in which a liquid photopolymer resin is selectively cured by a light source to build a three-dimensional part layer by layer. The process uses ultraviolet (UV) light or another controlled light source to solidify the resin within a vat. Stereolithography (SLA) and Digital Light Processing (DLP) are examples of vat photopolymerization technologies.

Related Terms: Digital Light Processing (DLP), Photopolymer, Resin, Stereolithography (SLA), Ultraviolet (UV) Curing

Velo3D

Velo3D is a manufacturer of industrial metal additive manufacturing systems based on Laser Powder Bed Fusion (LPBF) technology. The company’s systems are designed to produce complex metal components with reduced support requirements, making them well suited for aerospace, defense, energy, and other high-performance applications.

Related Terms: Laser Powder Bed Fusion (LPBF), Metal Additive Manufacturing, Support Structures

W

Warping

Warping is the unintended distortion or deformation of a part caused by internal stresses that develop during manufacturing or cooling. In additive manufacturing, warping is commonly associated with thermal stresses created as material is deposited or fused layer by layer. Factors such as material properties, build orientation, part geometry, and process parameters can influence the likelihood of warping. Proper design, process control, and support structures can help minimize distortion and improve dimensional accuracy.

Related Terms: Build Orientation, Heat Treat, Layer Thickness, Print Parameter, Support Structures

Y

Yield Strength

Yield Strength is the amount of stress a material can withstand before it begins to deform permanently. When the applied stress exceeds the yield strength, the material will not return to its original shape after the load is removed. Yield strength is a fundamental mechanical property used to evaluate a material’s suitability for structural and load-bearing applications.

Related Terms: Elastic Modulus, Mechanical Properties, Tensile Strength, Tensile Testing

#

3D Printing

3D Printing is the common term for additive manufacturing, a manufacturing process in which three-dimensional parts are produced by adding material layer by layer from a digital model. While “3D printing” is widely used in consumer, educational, and commercial contexts, additive manufacturing is the preferred technical term used by ASTM International, ISO, and much of the manufacturing industry.

Related Terms: Additive Manufacturing