A
Additive Manufacturing (AM)A family of manufacturing processes that create three-dimensional objects by adding material layer by layer, as opposed to subtractive methods that remove material from a solid block. Metal AM enables complex geometries impossible with traditional manufacturing.B
Build VolumeThe maximum physical dimensions (X, Y, Z) of parts that can be produced in a single build on an AM machine. Build volume varies by machine model and directly impacts the maximum part size and the number of parts that can be nested in a single build.D
DfAM (Design for Additive Manufacturing)A design methodology that leverages the unique capabilities of additive manufacturing processes. DfAM encompasses topology optimization, lattice structures, part consolidation, and design strategies that account for process-specific constraints such as overhang angles and minimum feature sizes.H
Hatch SpacingThe distance between adjacent laser scan tracks within a single layer. Hatch spacing, together with laser power, scan speed, and layer thickness, determines volumetric energy density and directly affects part density, surface quality, and mechanical properties.I
Inert AtmosphereA controlled gas environment (typically argon or nitrogen) maintained inside the build chamber during LPBF processing. The inert atmosphere prevents oxidation of the metal powder and melt pool, which is critical for achieving target material properties.L
LPBF (Laser Powder Bed Fusion)A metal additive manufacturing process in which a high-power laser selectively melts regions of a thin layer of metal powder spread across a build platform. The process repeats layer by layer to build three-dimensional metal parts. LPBF is the most widely adopted metal AM technology for production applications.M
Melt PoolThe localized region of molten metal created by the laser during LPBF processing. Melt pool size, shape, and stability are critical indicators of process quality. Monitoring melt pool characteristics enables real-time assessment of build integrity.O
Overhang AngleThe angle at which a surface extends from the build platform without direct support from previously built layers. Surfaces below a critical overhang angle (typically around 45 degrees from horizontal) require support structures to prevent deformation during building.P
Powder BedThe layer of metal powder spread uniformly across the build platform before laser exposure. Powder bed quality -- including layer thickness uniformity, powder distribution, and absence of defects -- directly impacts the quality of the final part.R
Residual StressInternal stresses that remain within a part after the LPBF build process due to rapid heating and cooling cycles. Residual stress can cause distortion, cracking, or reduced fatigue performance if not properly managed through process parameter optimization, scan strategy, and post-build heat treatment.S
Scan StrategyThe pattern and sequence in which the laser traverses each layer during LPBF. Common strategies include stripe, checkerboard, and island patterns. Scan strategy significantly influences residual stress distribution, microstructure, and surface quality.SinteringA thermal process in which powder particles bond together at temperatures below the melting point. While LPBF uses full melting, sintering-based AM processes (such as binder jetting with subsequent sintering) offer an alternative approach to metal part production. Support StructuresTemporary structures built alongside the part during the LPBF process to anchor overhanging features to the build platform, conduct heat away from the part, and prevent distortion. Support structures are removed during post-processing. T
Topology OptimizationA computational design method that optimally distributes material within a defined design space to meet structural requirements (loads, constraints, boundary conditions) while minimizing weight. The organic shapes produced by topology optimization are often only manufacturable through additive manufacturing.V
Volumetric Energy Density (VED)A parameter calculated from laser power, scan speed, hatch spacing, and layer thickness that represents the energy input per unit volume of material. VED is commonly used as a first-order indicator for comparing process parameter sets, though it does not capture all relevant physics of the melt pool.