Comparative sustainability assessment of powder bed fusion and solid-state additive manufacturing processes: The case of direct metal laser sintering versus additive friction stir deposition

Abstract

This work aims to conduct a comparative sustainability assessment between two promising additive manufacturing methods: additive friction stir deposition (AFSD) and direct metal laser sintering (DMLS). The comprehensive evaluation in this assessment accounts for environmental, economic, and social dimensions, incorporating life cycle global warming potential, water footprint, and energy demand of the materials used. Key performance indicators are also used to rank these processes, employing various Multi-Criteria Decision-Making techniques. The findings of the study reveal that AFSD exhibits superior sustainability when compared to DMLS, with AFSD achieving a sustainability score of 69%, while DMLS lags behind at 31%. Notably, the sensitivity analysis elucidates that the variance in build volume between the two methods exerts the most substantial influence on the sustainability score, accounting for a 4.2% difference. Additionally, production speed plays a pivotal role in determining sustainability outcomes. On the other hand, mechanical properties have the least impact on the overall results. This outcome can be attributed to the marginal disparities in ultimate tensile strength, yield strength, and hardness exhibited by both AFSD and DMLS.