中国物理B ›› 2024, Vol. 33 ›› Issue (11): 116201-116201.doi: 10.1088/1674-1056/ad6cca
A molecular dynamics study on mechanical performance and deformation mechanisms in nanotwinned NiCo-based alloys with nano-precipitates under high temperatures
Zihao Yu(于子皓)1, Hongyu Wang(王鸿宇)1, Ligang Sun(孙李刚)2, Zhihui Li(李志辉)3,4, and Linli Zhu(朱林利)1,†
- 1 School of Aeronautics and Astronautics, Center for X-Mechanics, Zhejiang University, Hangzhou 310027, China;
2 School of Science, Harbin Institute of Technology, Shenzhen 518067, China;
3 Hypervelocity Aerodynamics Institute, China Aerodynamics Research and Development Center, Mianyang 621000, China;
4 National Laboratory for Computational Fluid Dynamics, Beijing 100191, China
A molecular dynamics study on mechanical performance and deformation mechanisms in nanotwinned NiCo-based alloys with nano-precipitates under high temperatures
Zihao Yu(于子皓)1, Hongyu Wang(王鸿宇)1, Ligang Sun(孙李刚)2, Zhihui Li(李志辉)3,4, and Linli Zhu(朱林利)1,†
- 1 School of Aeronautics and Astronautics, Center for X-Mechanics, Zhejiang University, Hangzhou 310027, China;
2 School of Science, Harbin Institute of Technology, Shenzhen 518067, China;
3 Hypervelocity Aerodynamics Institute, China Aerodynamics Research and Development Center, Mianyang 621000, China;
4 National Laboratory for Computational Fluid Dynamics, Beijing 100191, China
摘要： Molecular dynamics simulations are performed to investigate the mechanical behavior of nanotwinned NiCo-based alloys containing coherent L1$_{2}$ nano-precipitates at different temperatures, as well as the interactions between the dislocations and nano-precipitates within the nanotwins. The simulation results demonstrate that both the yield stress and flow stress in the nanotwinned NiCo-based alloys with nano-precipitates decrease as the temperature rises, because the higher temperatures lead to the generation of more defects during yielding and lower dislocation density during plastic deformation. Moreover, the coherent L1$_{2}$ phase exhibits excellent thermal stability, which enables the hinderance of dislocation motion at elevated temperatures via the wrapping and cutting mechanisms of dislocations. The synergistic effect of nanotwins and nano-precipitates results in more significant strengthening behavior in the nanotwinned NiCo-based alloys under high temperatures. In addition, the high-temperature mechanical behavior of nanotwinned NiCo-based alloys with nano-precipitates is sensitive to the size and volume fraction of the microstructures. These findings could be helpful for the design of nanotwins and nano-precipitates to improve the high-temperature mechanical properties of NiCo-based alloys.
中图分类号: (Deformation and plasticity)
- 62.20.F-