Analysis of Surface State after Turning of High Tempered Bearing Steel.

This paper investigates surface state after turning of the high tempered bearing steel 100Cr6 with a hardness of 40 HRC. White layer (WL) thickness and its microhardness, as well as surface roughness, are investigated as a function of tool flank wear as well as cutting speed . The mechanical and thermal load of the machined surface were analysed in order to provide a deeper insight into their superimposing contribution. Cutting energy expressed in terms of cutting force was analyses as that consumed for chip formation and consumed in the flank wear land . It was found that the mechanical energy expressed in terms of the shear components of the grows with , converts to the heat and strongly affects the thickness of the re-hardened layer. Furthermore, the superimposing contribution of the heat generation and its duration in the region should also be taken into account. It was also found that the influence of predominates over the variable cutting speed.