Effect of Grinding Parameters on the Hardness Penetration Depth of the Steel GCr15 in Internal Grind Hardening Process

Abstract This paper discusses the effects of the depth of cut (ap ), the workpiece speed (vw ) and the grinding wheel speed (vs ) on the structure and hardness of the grind hardening layer on the steel GCr15. It was found that the completely hardened zone of the internal grind-hardened layer on the steel GCr15 mainly contains needle-shaped martensite and a very low amount of carbides and retained austenite. The grinding parameters have no significant effect on the martensite microstructure and hardness of the high-hardness zone in the internal grind-hardening process. An increase of the depth of cut and the grinding wheel speed or a decrease of the workpiece speed, leads to a thicker grind-hardening layer. From the viewpoint of increasing the hardness penetration depth, a larger the depth of cut and the grinding wheel speed and a smaller the workpiece speed should be selected, under the internal grind-hardening experimental conditions.