Sustainability analysis of additive + subtractive manufacturing processes for Inconel 625

Abstract

With the purpose to analyse the interrelations between the additive and the subtractive processes, this novel study does a comprehensive and comparative analysis of Wire Arc Additively Manufactured Inconel 625 (IN625) with its wrought counterpart. The fabrication, as well as the machining stage, is analyzed in terms of economic, environmental and machinability aspects. The machinability analysis is conducted based on power consumption, surface roughness and tool wear under Dry, Cryogenic and Electrostatic Minimum Quantity Lubrication (EMQL) cutting environments. The economic viability of additively manufactured and wrought Inconel 625 is assessed by comparing the total fabrication and machining costs, whereas the long-term viability of the fabrication and machining process and the cutting environments is analyzed by assessing the effects of carbon emissions on sustainability. The comprehensive analysis showed that the fabrication cost of AMed IN625 was found to be about 86.62% more than that of wrought component and the total machining costs increased by 5.51%, 37.43%, and 61.605% for machining AMed IN625 in comparison to wrought IN625 for dry, EMQL, and LCO2 cutting environments. The total carbon emissions from fabrication as well as machining of AMed IN625, also increased by about 123.95%, 79.43%, and 60.60% for dry, EMQL, and LCO2 cutting environments respectively as compared to wrought IN625. The tool life while machining AMed IN625 increased by about 191.55%, 115.80%, and 65.95% for dry, EMQL, and LCO2 respectively whereas there was a 1.741% and 8.522% increase in the power consumption values for dry and LCO2 environment as compared to wrought IN625.