A modified Johnson-Cook constitutive model for improved thermal softening prediction of machining simulations in C45 steel

A new modified Johnson-Cook model is developed to capture the non-linear thermal softening behaviour below austenite transformation temperature (723°C) in C45 ferritic-pearlitic steel, which not captured by original (JC) model. The physical mechanisms responsible for this are also studied. experimental quasi-static and high strain rate axisymmetric compression testing from 20°C 720°C implemented into 3D finite element drilling simulations. improvement over JC demonstrated comparison experimentally measured torque thrust force.