Loreta Pomenić

Mathematical modelling and computer simulation of mechanical properties of quenched and tempered steel

A mathematical model and method of computer simulation for the prediction of mechanical properties of quenched and tempered steel were developed. Numerical modelling of hardness distribution in as-quenched steel components was performed based on experimental results of Jominy test. Modified Jominy test was designed for hardenability prediction of high-hardenability steels. Hardness of quenched and tempered steel was expressed as a function of maximal hardness of actual steel and representatives of chemical diffusivity of steel according to the time and temperature of tempering. Yield strength and fracture toughness distributions were estimated using the Hahn−Rosenfield approach. Fatigue resistance was estimated based on predicted microstructure and hardness. Distribution of other relevant mechanical properties was found out based on predicted as-quenched and tempered hardness of steel. Experimental investigation was performed on high-hardenability steel for tools and dies. The established procedure was applied in computer simulation of mechanical properties of a quenched and tempered steel workpiece.