A Comparison between Powder Bed Fusion of Polyamide 12 and Aluminum Computer Numeric Control Machining: A Carbon Footprint and Energy Assessment

Abstract

This study presents a comparative life cycle assessment (LCA) of two manufacturing scenarios for a camera housing: Powder Bed Fusion (PBF) using polyamide 12 (PA-12) and Computer Numeric Control (CNC) machining using aluminum, for a cradle-to-gate boundary. The selected impact categories were cumulative energy demand (CED) and global warming potential (GWP). The key findings indicate that the PA-12 PBF part outperformed the aluminum CNC machining one in terms of environmental and energy performance, showing a significant reduction of approximately 90% in equivalent carbon emissions and 84% in cumulative energy demand. Sensitivity analyses revealed that the PBF process was highly sensitive to changes in the proportion of virgin/recycled material for the printing process, variations in the life cycle inventory (LCI) data sources for PA-12 powder production, and changes in the transportation system for imported materials, as is the case for the main input in the process (PA-12 powder). Sensitivity analysis also showed less impact for the PBF camera housing even considering a lifespan of one-fifth that of the aluminum for the impact categories considered. However, it should be noted that this analysis did not include considerations for the usage and end-of-life phases, which may have significant contributions to the overall environmental impact.