中国物理B ›› 2020, Vol. 29 ›› Issue (3): 36201-036201.doi: 10.1088/1674-1056/ab7440

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

First-principles investigation on ideal strength of B2 NiAl and NiTi alloys

Chun-Yao Zhang(张春尧), Fu-Yang Tian(田付阳), Xiao-Dong Ni(倪晓东)   

  1. Institute for Applied Physics, University of Science and Technology Beijing, Beijing 100083, China
  • 收稿日期:2019-08-07 修回日期:2019-12-30 出版日期:2020-03-05 发布日期:2020-03-05
  • 通讯作者: Fu-Yang Tian, Xiao-Dong Ni E-mail:fuyang@ustb.edu.cn;nixiaodong@ustb.edu.cn
  • 基金资助:

    Project supported by the Science Challenge Project, China (Grant No. TZ2018002) and the Fundamental Research Funds for the Central Universities, China (Grant No. FRF-TP-18-013A3).

First-principles investigation on ideal strength of B2 NiAl and NiTi alloys

Chun-Yao Zhang(张春尧), Fu-Yang Tian(田付阳), Xiao-Dong Ni(倪晓东)   

  1. Institute for Applied Physics, University of Science and Technology Beijing, Beijing 100083, China
  • Received:2019-08-07 Revised:2019-12-30 Online:2020-03-05 Published:2020-03-05
  • Contact: Fu-Yang Tian, Xiao-Dong Ni E-mail:fuyang@ustb.edu.cn;nixiaodong@ustb.edu.cn
  • Supported by:

    Project supported by the Science Challenge Project, China (Grant No. TZ2018002) and the Fundamental Research Funds for the Central Universities, China (Grant No. FRF-TP-18-013A3).

摘要:

For B2 NiAl and NiTi intermetallic compounds, the ideal stress-strain image is lack from the perspective of elastic constants. We use first-principles calculation to investigate the ideal strength and elastic behavior under the tensile and shear loads. The relation between the ideal strength and elastic constants is found. The uniaxial tension of NiAl and NiTi along <001> crystal direction leads to the change from tetragonal path to orthogonal path, which is driven by the vanishing of the shear constant C66. The shear failure under {110}<111> shear deformation occurring in process of tension may result in a small ideal tensile strength (~2 GPa) for NiTi. The unlikeness in the ideal strength of NiAl and NiTi alloys is discussed based on the charge density difference.

关键词: ideal strength, stress-strain, elastic constants, first-principles calculation, NiAl and NiTi, charge density difference

Abstract:

For B2 NiAl and NiTi intermetallic compounds, the ideal stress-strain image is lack from the perspective of elastic constants. We use first-principles calculation to investigate the ideal strength and elastic behavior under the tensile and shear loads. The relation between the ideal strength and elastic constants is found. The uniaxial tension of NiAl and NiTi along <001> crystal direction leads to the change from tetragonal path to orthogonal path, which is driven by the vanishing of the shear constant C66. The shear failure under {110}<111> shear deformation occurring in process of tension may result in a small ideal tensile strength (~2 GPa) for NiTi. The unlikeness in the ideal strength of NiAl and NiTi alloys is discussed based on the charge density difference.

Key words: ideal strength, stress-strain, elastic constants, first-principles calculation, NiAl and NiTi, charge density difference

中图分类号:  (Elastic moduli)

  • 62.20.de
64.70.qd (Thermodynamics and statistical mechanics) 74.20.Pq (Electronic structure calculations)