Life cycle assessment to establish sustainable cutting fluid strategy for drilling Ti-6Al-4V

Abstract

This innovative experimental work compares the machining performance of cryogenic machining using LCO2 and LN2 with conventional mineral-based flood machining for drilling Ti-6Al-4V to establish a sustainable cutting fluid strategy. In this context, machining performance indicators like surface roughness in Ra, Active Cutting Energy (ACE), Active Energy Consumed by Machine Tool (AECMT), and Energy Efficiency (EE) have been analyzed for each three cutting conditions. Also, ReCiPe midpoint 2016 (H) has been employed to perform LCA examination and measure the impact of drilling Ti-6Al-4V on natural resources, human health, and ecosystem. The range for the values of Ra has been found as 0.6–0.78 μm, 0.56–0.72 μm, and 0.75–0.8 μm for flood, LCO2, and LN2 as cutting fluids respectively when the cutting speed and feed rate are 80 m/min and 100 mm/min respectively. The increased values of ACE and AECMT with lesser values of EE have been found for flood machining in comparison with cryogenic machining. The results of LCA suggest that 67–99% of the whole impacts on ecology due to three cutting conditions are generated by flood machining only. Thus, cryogenic machining using LCO2 and LN2 has been emerged as sustainable cutting fluid strategies as a substitute for polluted mineral-based flood coolant.