中国物理B ›› 2026, Vol. 35 ›› Issue (1): 17102-017102.doi: 10.1088/1674-1056/ae1e68

• • 上一篇    下一篇

Sequential phase transformations in Ta0.4Ti2Zr alloy via tensile molecular dynamics simulations with deep potential

Hongyang Liu(刘洪洋)1,2,3, Rong Chen(陈荣)1, Bo Chen(陈博)1,2,3,†, Jingzhi He(贺靖之)4, Dongdong Kang(康冬冬)1,2,3, and Jiayu Dai(戴佳钰)1,2,3,‡   

  1. 1 College of Science, National University of Defense Technology, Changsha 410073, China;
    2 Hunan Key Laboratory of Extreme Matter and Applications, National University of Defense Technology, Changsha, 410073, China;
    3 Hunan Research Center of the Basic Discipline for Physical States, National University of Defense Technology, Changsha 410073, China;
    4 College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China
  • 收稿日期:2025-10-11 修回日期:2025-11-08 接受日期:2025-11-12 发布日期:2025-12-30
  • 通讯作者: Bo Chen, Jiayu Dai E-mail:chenbochain@nudt.edu.cn;jydai@nudt.edu.cn
  • 基金资助:
    This work was supported by the National University of Defense Technology Research Fund Project, the National Natural Science Foundation of China (Grant No. 12534013), and the Science and Technology Innovation Program of Hunan Province (Grant Nos. 2025ZYJ001 and 2021RC4026).

Sequential phase transformations in Ta0.4Ti2Zr alloy via tensile molecular dynamics simulations with deep potential

Hongyang Liu(刘洪洋)1,2,3, Rong Chen(陈荣)1, Bo Chen(陈博)1,2,3,†, Jingzhi He(贺靖之)4, Dongdong Kang(康冬冬)1,2,3, and Jiayu Dai(戴佳钰)1,2,3,‡   

  1. 1 College of Science, National University of Defense Technology, Changsha 410073, China;
    2 Hunan Key Laboratory of Extreme Matter and Applications, National University of Defense Technology, Changsha, 410073, China;
    3 Hunan Research Center of the Basic Discipline for Physical States, National University of Defense Technology, Changsha 410073, China;
    4 College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China
  • Received:2025-10-11 Revised:2025-11-08 Accepted:2025-11-12 Published:2025-12-30
  • Contact: Bo Chen, Jiayu Dai E-mail:chenbochain@nudt.edu.cn;jydai@nudt.edu.cn
  • Supported by:
    This work was supported by the National University of Defense Technology Research Fund Project, the National Natural Science Foundation of China (Grant No. 12534013), and the Science and Technology Innovation Program of Hunan Province (Grant Nos. 2025ZYJ001 and 2021RC4026).

摘要: Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys (MPEAs) requires high-fidelity atomic-scale simulations. This study develops a deep potential (DP) model to enable molecular dynamics simulations of the Ta$_{0.4}$Ti$_{2}$Zr (Ta$_{0.4}$) alloy. Monte Carlo simulations using this potential reveal Ta atom precipitation in the Ta$_{0.4}$ alloy. Under uniaxial tensile loading along the [100] direction in the NPT ensemble, the alloy undergoes a remarkable sequence of phase transformations: an initial body-centered cubic (BCC$_{1}$) to face-centered cubic (FCC) transformation, followed by a reverse transformation from FCC to a distinct BCC phase (BCC$_{2}$), and finally a BCC$_{2}$ to hexagonal close-packed (HCP) transformation. Critically, the reverse FCC to BCC$_{2}$ transformation induces significant volume contraction. We demonstrate that the inversely transformed BCC$_{2}$ phase primarily accommodates compressive stress. Concurrently, the reorientation of BCC$_{2}$ crystals contributes substantially to the observed high strain hardening. These simulations provide atomic-scale insights into the dynamic structural evolution, sequential phase transformations, and stress partitioning during deformation of the Ta$_{0.4}$ alloy. The developed DP model and the revealed mechanisms offer fundamental theoretical guidance for accelerating the design of high-performance MPEAs.

关键词: multi-principal element alloys, machine-learning potential, phase transformation, stress partitioning

Abstract: Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys (MPEAs) requires high-fidelity atomic-scale simulations. This study develops a deep potential (DP) model to enable molecular dynamics simulations of the Ta$_{0.4}$Ti$_{2}$Zr (Ta$_{0.4}$) alloy. Monte Carlo simulations using this potential reveal Ta atom precipitation in the Ta$_{0.4}$ alloy. Under uniaxial tensile loading along the [100] direction in the NPT ensemble, the alloy undergoes a remarkable sequence of phase transformations: an initial body-centered cubic (BCC$_{1}$) to face-centered cubic (FCC) transformation, followed by a reverse transformation from FCC to a distinct BCC phase (BCC$_{2}$), and finally a BCC$_{2}$ to hexagonal close-packed (HCP) transformation. Critically, the reverse FCC to BCC$_{2}$ transformation induces significant volume contraction. We demonstrate that the inversely transformed BCC$_{2}$ phase primarily accommodates compressive stress. Concurrently, the reorientation of BCC$_{2}$ crystals contributes substantially to the observed high strain hardening. These simulations provide atomic-scale insights into the dynamic structural evolution, sequential phase transformations, and stress partitioning during deformation of the Ta$_{0.4}$ alloy. The developed DP model and the revealed mechanisms offer fundamental theoretical guidance for accelerating the design of high-performance MPEAs.

Key words: multi-principal element alloys, machine-learning potential, phase transformation, stress partitioning

中图分类号:  (Molecular dynamics calculations (Car-Parrinello) and other numerical simulations)

  • 71.15.Pd
61.66.Dk (Alloys ) 02.70.Ns (Molecular dynamics and particle methods) 64.75.Nx (Phase separation and segregation in solid solutions)