Grinding of Glass: The Mechanics of the Process

An investigation of the material removal process in grinding glass and the effects of the grinding process on the surface structure and fracture strength of the finished product is reported in two papers. This first paper is concerned with the mechanics of material removal for grinding a large number of glasses and some glass-ceramics over a wide range of operating conditions with both silicon carbide and diamond grinding wheels. Experimental results indicate that the specific grinding energy generally increases with the softening temperature of the glass, and is an order of magnitude smaller for grinding with diamond wheels than for grinding with silicon carbide wheels. From observations of individual grinding scratches and an analysis of the experimental results, it is concluded that virtually all of the grinding energy is expended by viscous deformation. Material removal occurs by flow into chips with silicon carbide abrasive and by brittle fracture preceded by viscous deformation with diamond abrasive. The specific grinding energy with diamond is much less than with silicon carbide, since a much smaller volume of material undergoes viscous deformation when grinding with diamond.