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The compositional-dependent phase engineering in TiZrHfNbx multi-principal element alloy
Yiwei Wanga,b, Quanfeng Hea,*, Yu Liaoa, Xufeng Wanga, Fenglin Luoc, Qing Wangc, Chuanwei Lia,b, Jianfeng Gua,b,*
aInstitute of Materials Modification and Modelling, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
bShanghai Key Laboratory of Materials Laser Processing and Modification, Shanghai Jiao Tong University, Shanghai 200240, China
cInstitute of Materials, Shanghai University, Shanghai 200072, China
Abstract
Phase engineering of Ti-/Zr-/Hf- alloys is critical for next-generation structural materials, yet the lack of understanding of composition-driven phase evolution and its kinetics impedes their design. This study investigates the phase transition pathways and kinetics in TiZrHfNbx (x = 0–0.4) alloys, revealing the influence of Nb content on phase stability and transition mechanisms. Multi-scale analyses have proven that Nb addition drives HCP (α)→BCC (β) transition, lowering α→β temperature while increasing activation energy. Two distinct transition pathways, β→α (Burgers mechanism) and β→ω (collapse mechanism), are identified. Intermediate ω-phase precipitation occurs via two modes: quenched athermal (ωath) through a diffusionless process, and aged isothermal (ωiso) companied with solute redistribution. A quantitative correlation between composition, phase constitution, and kinetics is established, providing insights into nonequilibrium phase transitions in multicomponent alloys. The reported phase transition mechanisms involving BCC↔HCP / BCC↔ω offering a framework for phase engineering in TiZrHfNb-based systems.
The compositional-dependent phase engineering in TiZrHfNbx multi-principal element alloy.pdf
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