FINITE ELEMENT MODELLING OF THE TURNING OF QUENCHED STEELS

The aim of the present paper is to study the capability of modelling by the Finite Element Method (FEM) when modelling behaviour of hard turning of 42CrMoS4 tempered steel, 60 HRC hardness, when machining with a PCBN tool. An analytical and experimental study has been carried out to analyse the effect of cutting parameters on variables such as cutting and feed force, temperature on the cutting zone, contact length and chip morphology. Initially, a flow stress model has been developed by carrying out dynamic and static compression tests at a high temperatures, obtaining the flow stress parameters to be implemented on the FEM model. Then, a 2D orthogonal cutting FEM model has been developed in the commercial software DEFORM. Finally, a series of experimental tests were devoted to the validation of the accurateness of the FEM model. In summary, the tendencies of the predictive model and experiments match in forces and temperatures. Major differences were found for contact length and chip thickness. Key Words: Hard turning, FEM, flow stress model, orthogonal test, machining, 42CrMoS4, PCBN