Finite Element simulation coupled to optimisation stochastic process to assess the effect of heat treatment on the mechanical properties of 42CrMo4 steel

The present study aims at studying the influence of heat treatment on the mechanical performance of 42CrM04 steel. Heat treatment is conduced in a way to affect significantly the microstructure, more precisely the tempered martensite structure. Tempering temperature is varied between 200 and 600° C. Experimental testing includes the determination of tensile properties and hardness scores. The identification of the mechanical parameters associated to elastic–plastic behaviour is undertaken using Finite Element computation to quantify the effect of heat treatment. The predictions show that characterisation of the material behaviour can be approached using a bilinear hardening model. The tempering temperature has a significant effect on the yield stress and tangent modulus.

► Combine on-line optimisation/Finite Element approach to identify mechanical behaviour.
► A reliable approach to derive adequate mechanical model for the studied steel.
► Simple elastoplastic model that allows direct correlation to the temperature effect.
► Stochastic search is relevant to obtain the true mechanical parameters.