Improving the Performance of Machining Parameters in the Turning Process of Inconel 686 by Using Cryo‐MQL Method

ABSTRACT Regarding its wide range of applications in different industries, such as oil and gas, and for manufacturing equipment used to control pollution and recycle industrial wastes, Inconel 686 turning process is highly important. The alloy is highly resistant to high temperatures and corrosion, and thus it can preserve its properties at high temperatures. Due to its low heat transfer coefficient and work hardening during operation, Inconel 686 is considered a difficult‐to‐cut material, and hence, turning Inconel 686 is challenged with major limitations regarding input parameter level and cutting fluid and issues such as reduced surface quality. The input parameter level and cutting fluid limitations might severely harm the environment and humans, decrease the machining efficiency and keep cleaner production goals out of reach. Novel cooling methods such as cryo‐MQL can contribute to achieving cleaner production goals. Cooling methods improve the machining performance and prohibit any damage to the surface integrity. In this study, cryo‐MQL, along with carbide‐coated tools and biodegradable vegetable oil, was adopted. The efficiency and success rate of cryo‐MQL were evaluated by comparing the results with those of MQL and wet methods. A wide range of output parameters, such as residual stresses, cutting zone temperature, cutting forces, tool wear, surface smoothness, surface defects and micro‐hardness, were assessed by changing the cutting speed and feed rate. The results indicated that cryo‐MQL could reduce the cutting forces, tool wear rate, cutting zone temperature and residual stresses while improving the surface quality. Moreover, environmental concerns were completely dealt with. Due to the increased possibility of higher input parameter levels, the time and cost of the cutting process were significantly reduced.