Experimental and theoretical investigation into surface roughness and residual stress using ball end magnetorheological finishing

Abstract

The generation of residual stresses by grinding process on the surface for a soft material results in poor performance and diminished life. In this paper, grinding-induced residual stresses is addressed and an attempt is made to relieve these residual stresses while achieving nano level surface finish using ball end magnetorheological finishing (BEMRF) process. BEMRF is a recently developed process that is effectively used to for fine figuring and polishing of a variety of magnetic and non-magnetic materials. In our present work we will demonstrate the relieving of residual stresses and reduction in surface roughness generated after surface grinding of Aluminium 7075 workpiece using BEMRF process. The impact of various BEMRF variables on reduction in surface roughness and residual stresses are discussed statistically and graphically. Residual stresses of workpiece surfaces have been measured by using portable X-ray residual stress analyzer. Significant process parameters affecting the residual stresses during polishing of workpiece are obtained using Analysis of variance (ANOVA) and F-test. It has been observed that reduction in residual stress is achieved along with nano level surface finish on aluminium workpiece surface using BEMRF technique.