The dynamic recrystallization behavior of 25CrMo4 steel was systematically investigated by compression deformation at different temperatures and strain rates on a Gleeble 1500 thermal mechanical simulation tester. The...The dynamic recrystallization behavior of 25CrMo4 steel was systematically investigated by compression deformation at different temperatures and strain rates on a Gleeble 1500 thermal mechanical simulation tester. The flow curves under different deformation conditions were obtained, and the effects of deformation temperature and strain rate on the appearance of the flow curves were discussed. Based on the experimental flow curves, the activation energy determined by regression analysis was Q = 337 kJ/mol, and the constitutive model was constructed. All the characteristic points of the flow curves were identified from the work hardening rate curves （θ= dσ/dε vs σ）, which were derived from the flow curves. Then, the kinetics model of dynamic recrystallization was determined by combining the Avrami equation with the stress loss resulted from the dynamic recrystallization. With the aid of the kinetics model, the effect of strain on the efficiency of power dissipation was discussed. Furthermore, the optimum parameters for the forging process were determined based on the processing maps.展开更多
The static recrystallization behavior of 25CrMo4 mirror plate steel has been determined by hot compression testing on a Gleeble 1500 thermal mechanical simulation tester. Compression tests were performed using double ...The static recrystallization behavior of 25CrMo4 mirror plate steel has been determined by hot compression testing on a Gleeble 1500 thermal mechanical simulation tester. Compression tests were performed using double hit schedules at temperatures of 950-- 1 150 ~C, strain rates of 0.01--0.5 s-1 , and recrystallization time of 1--100 s. Results show that the kinetics of static recrystallization and the microstructural evolution were greatly influenced by the deformation parameters （deformation temperature, strain rate and pre strain） and the initial austenite grain size. Based on the experimental results, the kinetics model of static recrystallization has been generated and the comparison between the experimental results and the predicted results has been carried out. It is shown that the predicted results were in good agreement with the experimental results.展开更多
基金financially supported by the National Basic Research Program of China(No.2011CB012903)
文摘The dynamic recrystallization behavior of 25CrMo4 steel was systematically investigated by compression deformation at different temperatures and strain rates on a Gleeble 1500 thermal mechanical simulation tester. The flow curves under different deformation conditions were obtained, and the effects of deformation temperature and strain rate on the appearance of the flow curves were discussed. Based on the experimental flow curves, the activation energy determined by regression analysis was Q = 337 kJ/mol, and the constitutive model was constructed. All the characteristic points of the flow curves were identified from the work hardening rate curves （θ= dσ/dε vs σ）, which were derived from the flow curves. Then, the kinetics model of dynamic recrystallization was determined by combining the Avrami equation with the stress loss resulted from the dynamic recrystallization. With the aid of the kinetics model, the effect of strain on the efficiency of power dissipation was discussed. Furthermore, the optimum parameters for the forging process were determined based on the processing maps.
基金sponsored by National Basic Research Program of China (2011CB012903)
文摘The static recrystallization behavior of 25CrMo4 mirror plate steel has been determined by hot compression testing on a Gleeble 1500 thermal mechanical simulation tester. Compression tests were performed using double hit schedules at temperatures of 950-- 1 150 ~C, strain rates of 0.01--0.5 s-1 , and recrystallization time of 1--100 s. Results show that the kinetics of static recrystallization and the microstructural evolution were greatly influenced by the deformation parameters （deformation temperature, strain rate and pre strain） and the initial austenite grain size. Based on the experimental results, the kinetics model of static recrystallization has been generated and the comparison between the experimental results and the predicted results has been carried out. It is shown that the predicted results were in good agreement with the experimental results.
