Environmental assessment of Selective Laser Melting compared with Laser Cutting of 316L stainless steel: A case study for flat washers' production

In industrial practise, decision makers should know performance characteristics, cost- and energy-related impacts for choosing the most suitable manufacturing technology for a specific product. In this context, the present work focuses on a technical, economic and environmental evaluation of the Selective Laser Melting processing of 316L stainless steel flat washers compared with the industrial CO2 Laser Cutting. The SLM process allows obtaining components with improved mechanical performance, with an increase of 15% and 48% in tensile strength and hardness, respectively. While surface roughness is more than 11 times worse than the hot rolled samples. The economic analysis showed the greater costeffectiveness of the LC technology, ensuring the production of a single component at the price of 0.63 s, against 45.13 s necessary for the SLM, which is mainly due to the high consumption of the assistant gas (i.e. Argon). The health and environmental impacts evaluation showed that the LC is around 2.5 times more eco- and human-friendly if compared with the SLM process. In particular, the most relevant damage effect is given by the depletion of the fossil fuels due to a high electricity consumption. However, the observed trend between the two technologies appears to be very similar, thus revealing the possibility of reducing the impact potentials associated to the SLM process with its continuous technological advancements, by making the process itself able to move from small to medium or high volume production rates. (C) 2020 CIRP.