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.
基金
supported by the National University of Defense Technology Research Fund Project
the National Natural Science Foundation of China(Grant No.12534013)
the Science and Technology Innovation Program of Hunan Province(Grant Nos.2025ZYJ001 and 2021RC4026)。