Comparison Research on the Machinability of Hardened Steel when Dry Turning with Ceramic and CBN Cutting Tools

Researching on dry turning hardened steel was to replace the grinding with turning, which would improve efficiency and reduce cost. The contrast experiments of turning hardened steel with ceramic and CBN cutting tools were carried out. The cutting forces of two tools with different cutting parameters were measured by Kistler cutting force acquisition system. The difference with two chips was observed by scanning electron microscope(SEM). The experimental equations of cutting forces were built up by the linear regression analysis method. The results indicated that the variation trend of cutting forces with ceramic and CBN cutting tools in same conditions was same. The thrust force was maximal, next was tangential force, axial force was minimum. The thrust force and tangential force of ceramic cutting tools were almost double compared with CBN cutting tools. The shapes of chips with ceramic and CBN cutting tools were saw-tooth, the rough slice layer with periodic flow was shown on outer surface and the friction mask was distributed well-proportioned on inner surface. The spacing of rough slice layer of chips with CBN cutting tools was more wide, the friction mask of chips with ceramic cutting tools was more clear.