Study of static recrystallization kinetics in a low alloy steel

In order to study the workability and optimize hot formation processing parameters for 42CrMo steel, the static recrystallization behaviors in 42CrMo steel were investigated by isothermal interrupted hot compression tests on Gleeble-1500 thermo-simulation machine. Compression tests were performed using double hit schedules at the temperatures from 850 °C to 1150 °C, strain rates from 0.01 s−1 to 1 s−1 and inter-stage delay time varying between 1 s and 100 s after the first stage. The kinetic equations have been proposed to predict the static recrystallization behaviors of hot deformed 42CrMo steel. Comparisons between the experimental and predicted results were carried out. Results show that the effects of deformation parameters, such as strain rate, deformation temperature and deformation degree, on the softening in multi-stage hot deformation are significant. The predicted results are in good agreement with the experimental ones, which indicates that the proposed kinetic equations can give an accurate estimate of the softening behaviors and microstructural evolutions for 42CrMo steel.