中國(guó)有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 33 No. 1 January 2023 |
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Non-ferrous Metal Materials Science and Engineering, Ministry of Education, Central South University, Changsha 410083, China;
3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
4. Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:Hot deformation behavior and microstructure of 60NiTi alloy during hot compressive deformation were investigated using Gleeble-3500 thermal simulation test machine in the temperature range of 500-650 °C and strain rate range of 0.001-1 s-1. The constitutive equation of hot compression was constructed and the hot processing maps were plotted. When the compression temperature rose or the strain rate declined, the peak stress reduced. The hot deformation activation energy was calculated as 327.89 kJ/mol, and the proper hot working parameters of compression temperature of 600-650 °C and strain rate of 0.005-0.05 s-1 were obtained. The recrystallization degree increased with increasing compression temperature. When the strain rate increased, both dislocation density and number of twins were improved, and the Ni3Ti phase tended to aggregate. Ni3Ti precipitation phase was beneficial to inducing dynamic recrystallization of the 60NiTi alloy. The dynamic recovery, dynamic recrystallization and twinning took place during hot compressive deformation of the 60NiTi alloy.
Key words: 60NiTi alloy; hot compressive deformation; microstructure; dynamic recrystallization
