Hot Deformation Behavior of 20CrMnTiH Steel Studied by Johnson-Cook Model and Genetic Algorithm

摘要

Hot compression tests of 20CrMnTiH steel are carried out in the strain rates range from O.Ols~(-1) to 10s~(-1) and in the temperature range from 973K to 1123K. The flow behaviors of 20CrMnTiH steel are described based on the analysis of true stress-true strain curves. The flow stress increases with the increasing of strain rate and the decreasing of deforming temperature. Johnson-Cook (J-C) model are used to analyze the hot deformation behaviors. In the constitutive model, material constants are determined based upon the experimental data. Genetic algorithm (GA) is proposed with the aim of optimizing the J-C model parameters. Good agreement is acquired by comparing of the experimental results with predicted results. It validates the efficiency of Johnson-Cook model in describing the material constitutive behavior.