Wear behavior of CBN tools while turning various hardened steels

An extensive study has been performed to investigate the tool-wear mechanisms of CBN cutting tools in finish turning of the following hardened steels: X155CrMoV12 (AISI D2) cold work steel, X38CrMoV5 (AISI H11) hot work steel, 35NiCrMo16 hot work steel and 100Cr6 bearing steel (AISI 52100), treated at 54 HRC. A large variation in tool-wear rate has been observed in machining of these steels. The generated tool flank grooves have been correlated with the hard carbide content of the workpieces. A crater wear study has also been performed and, it is shown that the appearance of an adhesive third body could induce a chemical wear in the tool.