Interfacial interactions between diamond disk and granite during vertical spindle grinding

The present work was undertaken to experimentally elucidate the interfacial interactions between diamond disk and workpiece during vertical spindle grinding of three natural granites. Measurements were made of the spindle power and the disk–granite interfacial temperatures using a pair of grindable foil thermocouples. The energy partition to the granite was subsequently estimated by using a temperature matching method. The ground granite surfaces were examined using SEM and XRD at each separate stage ranging from rough to fine grinding. The experimental results showed that maximum temperature rise at the disk–granite interface was unlikely to be a significant factor governing the formation of high gloss on the ground granite surfaces. New composition was not detected on the ground granite surfaces. SEM observations indicated that the granite workpieces were removed mainly by ductile mechanism, with some evidence of brittle fracture especially for rough grinding and to a much lesser extent for fine grinding. The gloss of a ground granite surface was found to be directly associated with the relative amount of ductile flow on the surface.