B12 Selection of Optimal Machining Parameters in Hard Turning with Graphite as Solid Lubricant(Advanced machining technology)

Abstract

In hard turning process, high temperatures are generated due to high hardness values of workpiece materials, which cause early tool wear. Tool wear not only reduces tool life, but also increases the forces and affects surface finish. Thus, an effective control of heat generated in the cutting zone is essential to ensure workpiece quality in hard turning process. However, due to the environmental restrictions, the use of cutting fluids is restricted. This paper deals with an investigation on using graphite as a solid lubricant to reduce the heat generated at the machining zone for improving the surface roughness of the bearing steel during the hard turning process. Experiments have been conducted to see the effect of machining parameters on the surface finish in solid lubricant assisted hard turning. Results indicate that there is a considerable improvement in the performance of hard turning using graphite as a solid lubricant when compared with dry hard turning in terms of surface quality. An attempt has also been made to select optimum machining parameters in hard turning with graphite as a solid lubricant.