Assessing the sustainability of laser powder bed fusion and traditional manufacturing processes using a parametric environmental impact model

Existing work on the relative environmental impacts of laser powder bed fusion (L-PBF) and traditional processes lacks generalizability as part design and machine settings change. We use literature reviews and power measurements to derive parametric environmental impact models with uncertainty for metal and polymer L-PBF process chains and traditional alternatives. Lead-time and cost models are derived as additional process selection metrics. The mechanistic models are functions of the part specification, batch size, and process settings. The results show the sensitivity of impacts to changes in part design/complexity and process settings is different for metal versus polymer L-PBF due to the process physics. Cradle-to-gate breakeven batch sizes (above which traditional manufacturing has lower impacts) are higher for lead-time and cost than environmental impacts, suggesting companies might increase impacts while saving time/costs. Life cycle accounting shows L-PBF enabled lightweighting, even with process improvement, falls short of environmental competitiveness for massproducing automotive parts.