Volumetric Energy Density
LPBFCalculate the volumetric energy density (VED) delivered to a powder bed during laser powder bed fusion, and check whether your parameter set falls inside the typical process window for common alloys.
Inputs
Typical window: 50–110 J/mm³ — Sweet spot ≈ 60–90 J/mm³; keyholing risk above ~120.
Results
P / v
P / (v · h)
Formula
VED is the laser power divided by the volumetric scan rate. It is a first-order proxy — useful for centering a parameter set, not a substitute for a melt-pool model.
VED = P / ( v · h · t )- P
- Laser power[W]
- v
- Scan speed[mm/s]
- h
- Hatch spacing[mm]
- t
- Layer thickness[mm]
Result is in J/mm³ when inputs are in the units above (W = J/s).
Interpretation
Below window
Insufficient melt-pool overlap → lack-of-fusion porosity, weak inter-layer bonding.
In window
Stable conduction-mode melt pool, near-full density (>99.5%) typically achievable.
Above window
Keyhole-mode melting → vapor depression, entrapped pore formation, possible spatter.
VED is necessary but not sufficient: two builds at the same VED can differ in density and microstructure because individual parameters govern melt-pool geometry, cooling rate, and Marangoni flow. Use VED for parameter centering and DOE planning — verify with cross-sections.
Sources
- [1]Gong, H. et al. — Influence of energy density on lack of fusion and keyhole porosity in SLM of Ti-6Al-4V — Additive Manufacturing 1–4 (2014) 87–98
- [2]Sing, S. L. & Yeong, W. Y. — Laser powder bed fusion for metal additive manufacturing: perspectives on recent developments — Virtual and Physical Prototyping 15:3 (2020) 359–370
- [3]ISO/ASTM 52900:2021 — Additive manufacturing — General principles — Fundamentals and vocabulary
Related tools
- Build-Time Estimator — layer-by-layer duration using VED parameters
- Support Volume Estimator — quantify support material and removal cost
- Melt-Pool Geometry — width, depth, and aspect ratio from VED inputs
- Fatigue Life Estimator — quantify how VED-driven porosity degrades fatigue life