Study on dynamic recrystallization models of 21-4N heat resistant steel

Abstract

The high-temperature deformation process and dynamic recrystallization (DRX) process of 21-4N were investigated under the conditions of the deformation temperature range of 1273 similar to 1453K, the strain rate range of 0.01 similar to 10s(-1) and the deformation degree of 60% (the total deformation is 0.916) by using Gleeble-1500D thermal simulated test machine. The curves of stress-strain (sigma-epsilon) were obtained, and the curves of work hardening rate (theta) and strain (epsilon) were obtained by taking derivative of sigma-epsilon. The DRX critical strains under different conditions were determined by the curves of work hardening rate (theta-epsilon), and the DRX critical strain model was established. The peak strains of 21-4N were obtained by the curves of sigma-epsilon, the relationship between peak stress (sigma(p)) and critical strain (epsilon(c)) was determined, and the peak strain model was established. The DRX volume fraction models of 21-4N were established by using Avrami equation. The DRX grain size of 21-4N was calculated by Image Pm Plus 6.0, and its DRX grain size models were established.