Enhancing the strength and ductility of a medium entropy alloy through non-basal slip activation

作者：Zhen Chen, Yang Chen, Daixiu Wei, Xu Liu, Xuan Luo, Henggao Xiang, Wu Gong, Stefanus Harjo, Takuro Kawasaki, Rui Hou, Jinpeng Zhang, De‐Min Zhu, Jiheng Tang, Li Luo, Jianghui Xie, Zheng Gong, Zhixiang Qi, H. W. Sheng, Guang Chen · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-61494-7 · 被引用次数：13 · 研究领域：High Entropy Alloys Studies、Additive Manufacturing Materials and Processes、Intermetallics and Advanced Alloy Properties

Developing alloys with both ultrahigh strength and ductility remains a formidable scientific challenge, primarily due to the inherent strength-ductility tradeoff. Here, we present an approach to enhance the ductility and strength of a medium-entropy alloy (MEA) featuring a fully recrystallized face-centered cubic/hexagonal close-packed dual-phase ultrafine-grained architecture. This is achieved by activating unusual non-basal slips in the ordered hexagonal close-packed superlattice nanoprecipitates, resulting in this MEA that exhibits remarkable uniform elongation (εu) and ultrahigh yield strength (σy) across a wide temperature range, particularly at cryogenic temperatures (σy ~ 2100 MPa, εu ~ 15%). The non-basal slips in the secondary phase are activated at ultrahigh stress levels, which are compatible with the increased yield strength of the MEA attained through multiple strengthening mechanisms, including grain boundaries, lattice friction, and second-phase nanoprecipitates provided by the multi-principal elements of the entropy alloy. The deformation mechanism elucidated in this work not only leverages the significant strengthening and strain hardening effects of brittle nanoprecipitates but also enables the ductilization of the alloy through sequential non-basal slip during ongoing deformation. The authors reveal the activation mechanism of non-basal slip systems in a medium entropy alloy, offering new insights for the design of advanced structural alloys with enhanced d...