Grey relational analysis coupled with principal component analysis for optimisation design of the process parameters in in-feed centreless cylindrical grinding

This paper investigates optimisation design of an in-feed centreless cylindrical grinding process performed on EN52 austenitic valve steel (DIN: X45CrSi93). The major performance characteristics selected to evaluate the process are surface roughness, out of cylindricity of the valve stem and diametral tolerance, and the corresponding centreless cylindrical grinding parameters are dressing feed, grinding feed, dwell time and cycle time. In this study, since the process is with multiple-performance characteristics, therefore, the grey relational analysis that uses grey relational grade as performance index is specially adopted to determine the optimal combination of centreless cylindrical grinding parameters. Moreover, the principal component analysis is applied to evaluate the weighting values corresponding to various performance characteristics so that their relative importance can be properly and objectively described. The results of confirmation experiments reveal that grey relational analysis coupled with principal component analysis can effectively be used to obtain the optimal combination of centreless cylindrical grinding parameters. Hence, this confirms that the proposed approach in this study can be a useful tool to improve the centreless cylindrical grinding performance of valve stem in in-feed centreless cylindrical grinding process.