The measurement of grinding temperatures at high specific material removal rates

Abstract

Developments in measuring surface temperatures during grinding at high specific material removal rates using PVD low melting point coatings are reported. This paper considers the use of this type of coating to determine the finished surface temperature and the thermal gradient below the workpiece surface under aggressive grinding conditions. Theoretical surface temperatures derived from mathematical modelling are compared to those measured by the PVD coating technique. Theoretical temperatures showed good correlation to the measured temperatures. Metallographic examination including Vickers microhardness testing was used to validate the measured thermal gradients and depth of phase transformations. The effect of the heating rate due to the grinding conditions was shown to have a significant influence on the A3 austenitic transition temperature. The technique of using low melting point PVD coatings is shown to offer a robust measurement technique for the determination of the finished surface temperature of a ground component, within aggressive environments and at high specific material removal rates.