Grinding and abrasive wear.

Abrasives are used in various forms to produce fine finishes on metal surfaces. Previously, grinding and abrasive processes have been studied in isolation; the present work however has shown that grinding can be usefully interpreted in abrasive wear terms. Wear experiments using small grinding wheels on a pin and ring machine have been able to reproduce many of the effects observed not only in grinding but also in such specialised processes as super-finishing. Abrasive wear theory has been re-examined, especially the parameters making up the K factor, and then applied to the grinding process. In order to test theoretical predictions a grinding dynamomoter was constructed to measure forces in surface grinding. Idealised indentors having simple geometrical shapes, similar to those assumed in abrasive wear theory, were tracked across smooth metal surfaces. Measurements of the seratches produced were then compared with theory. Scratch tests on a range of heat-treated steels using both idealised indentors and abrasive grits showed that pile-up at the edge of scratches is a highly significant factor in determining wear rate in abrasion and cutting forces in grinding. Finally a wide range of techniques for examining abrasives has been studied, the most notable of which involved the use of a scanning electron microscope.