Performance improvement of SiC grinding using solid lubricants

Heat produced during ceramic grinding, due to high specific energy and high wheel-workpiece friction, is critical in terms of workpiece quality. High heat generation at the grinding zone impairs the workpiece quality by inducing thermal damage in the form of surface and subsurface cracks, phase transformations, tensile residual stresses, etc. These damages can severely limit the application of ground ceramic components. Cooling and lubrication therefore, plays an important role during ceramic grinding. Conventional cutting fluids are often ineffective due to the phenomena like air barrier and film boiling effect. Further, these fluids have a direct influence both to human health and environment and therefore, being questioned in the light of economic and ecological manufacture. So, possible replacement of cutting fluids by something else is of great concern to the researchers in recent years. Demands for high operating temperatures, lower cost, longer life and better performance drive the search and use of alternative lubricants. This paper deals with an investigation on using graphite and molybdenum disulphide as solid lubricants, to reduce friction and heat generated at the grinding zone. An experimental setup has been developed, and experiments have been conducted to study the effect of using these lubricants, on tangential grinding force, specific energy and surface roughness while grinding SiC. Results indicate that there is a considerable improvement in the process performance with solid lubricant assisted grinding as compared to that of grinding in dry condition.