Modelling and Experimental Investigation of Cutting Temperature when Rough Turning Hardened Tool Steel with PCBN Tools

In this study the cutting tool temperature that develops during rough turning of hardened cold-work tool steel is modelled on the basis of experimental data. The data obtained from a series of thermocouples, placed on a PCBN insert, into an anvil, and into a toolholder, were used as the input for the model. An inverse problem was solved, where the heat fluxes and heat transfer coefficients were computed and where the developed temperature field was reconstructed from the experimental readings. The temperature was modelled for the case of new tools, as well as for the case of its development in the course of tool wear. The machining case involved utilization of a high-cBN content and a binderless PCBN grade, both possessing high thermal conductivity of 110 and 190 W/mK respectively.