On the feasibility of a reduction in cutting fluid consumption via spray of biodegradable vegetable oil with compressed air in machining Inconel 706

Abstract

Superalloys, such as Inconel 706, have extensive applications in aerospace and turbine manufacturing industries owing to their exceptional characteristics, especially high corrosion resistance and stability in elevated temperatures. However, they usually suffer from low coefficient of heat transfer, which can put them in the category of hard-machining alloys. Therefore, utilizing a cutting fluid is the indispensable part of superalloy machining process. Investigating the feasibility of reducing or even removing the cutting fluid plays a crucial role in the machining, since it may induce high machining costs, detrimental impacts on environment and endanger human health. In the present article, influences of machining parameters on forces, surface roughness and tool tip temperature were investigated in two modes of utilizing fluid, which were flood mode and spraying with compressed air, in order to reduce or eliminate the cutting fluid from turning process of Inconel 706. The results revealed that spray mode of cutting fluid in combination with compressed air can ameliorate the heat transfer problem. Moreover, in all of the experiments with spray mode, cutting forces, surface roughness and temperature of cutting area were significantly lower than using fluid with flood mode. This can result in a remarkable decrease in consumption of cutting fluid, which in turn, can solve the environmental issues. Furthermore, during machining with using cutting fluid in spray mode, it is possible to monitor the temperature of machining area via thermal imager in order to have an appropriate control over machining process. Eventually, optimum values of machining parameters were proposed for machining with spray mode of cutting fluid.