Composition and Strength-plasticity Optimization of TiZr-based High-entropy Alloy through Solid Solution Strengthening by Laser Directed Energy Deposition
Author of the article:WULiangyi1,2, YU Jun1,2, LIN Xin1,2, YAN Qiaodan1,2, WANG Linzeng1,2, NIU Yihao1,2
Author's Workplace:1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China; 2. Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi'an 710072, China
Key Words: laser-directed energy deposition; single-phase TiZr-based high-entropy alloy; balance of strength and plasticity; solution strengthening
Abstract:
Currently, some TiZr-based high-entropy alloys have difficulty balancing strength and plasticity because of the
large amount of brittle precipitation. This limitation hinders their engineering application as structural materials for complex
components. Laser-directed energy deposition (LDED) technology provides unique advantages in composition design
through the mixed element method and rapid nonequilibrium solidification. Therefore, the primary elements of the
TiZr-based high-entropy alloys in this study were adjusted, leading to the achievement of a nonequiatomic
Ti39
Zr39
Nb11
Mo5.5
V5.5
alloy with high relative density via LDED. Furthermore, a single-phase solid solution was obtained
without the precipitation of brittle phases. The alloy exhibits excellent plastic deformation capability, with a compressive
strain exceeding 50%. At a strain rate of 50%, the compressive stress reaches 2 194 MPa. Solid solution strengthening
contributes approximately 75% of the yield strength, which is crucial to the high strength of the alloy.