Cutting temperature force and roughness in high pressure coolant assisted hard turning

Abstract

Machining hardened steels has become un important manufacturing process, particularly in the automotive and bearing industries. Abrasive processes such as grinding have typically been required to machine hardened steels, but advances in machine tools and cl1tling materials have allowed hard turning on modem lathes to become a realistic replacement for many grinding applications. There are many advantages of hard turning, such as increased flexibility, decreased cycle times, reductions in machine tool cost,.>,und elimination of environmentally hazardous cutting fluids. Despite these advantages, implementation of hard turning remains relatively low, primarily due to concerns about the quality of hard turned surfaces and a lack of understanding about the wear behavior of cutting tools. The effects of high pressure coolant on cutting performances in respect of chip formation, cutting temperature, cutting forces and surfa<,;erouglmess have been studied using carbide insert. The same experiments were earried out on the above under dry condition in order to compare the results with those obtained under minimal clJtling fluid condition. The result indicated that the machining with high pressure coolant performed much better than dry machining mainly due to substantial reduction in cutting tcmperature enabling favorable chip-tool interaction. This also facilitated the reduction in cutting forees and surface finish.