A fully recrystallized heterogeneous grain structure with dispersed second phases for enhancing strength-ductility synergy in an Al-Cu-Mn alloy

Xiaoyu Bai, Linxiang Liu, Mengyan Fei, Jiaxi Zhu, Zhongsheng Yang, Kexuan Zhou, Dingcong Cui, Yue Li, Jincheng Wang, Xiaoguang Fan, Zhijun Wang

科研成果: 期刊稿件文章同行评审

2 引用 (Scopus)

摘要

Introducing heterogeneous grain structures has been demonstrated as an effective strategy to overcome the strength-ductility trade-off in metallic materials. Here, we designed a fully recrystallized heterogeneous microstructure via controlling local recrystallization around the grain boundaries coupled with the second phase. The representative feature of this microstructure is the topology of the nearest grain neighbors, where a fully recovered large grain is surrounded by multiple recrystallized small grains. Meanwhile, the second phase distribution around the grain boundary could be remarkably optimized during the processing. Within a commercial Al-Cu-Mn alloy, a remarkable ultimate tensile strength of 365 MPa with uniform elongation of 30 % was achieved through this heterogeneous structure, corresponding to an 18 % increase in ultimate tensile strength and a 29 % improvement in ductility compared with the uniform-grained counterpart. Characterized by quasi-in-situ EBSD, it was found that the multiple small grain neighbors coordinated local strain incompatibility near the hetero-interface by dislocation slips and local reorientations, which can better sustain the strain hardening. In situ tensile tests unveiled the micro-crack blunting by ductile large grains, endowing superior crack-arrest capability. Moreover, tailored dispersed Al2Cu particles inhibited inter-cluster void coalescence and interface-debonding by eliminating continuous crack growth paths, promoting stable damage evolution. These results give a new insight into the controllable design of heterogeneous-grained alloys with second phases for achieving superior combinations of mechanical properties.

源语言英语
文章编号175989
期刊Journal of Alloys and Compounds
1005
DOI
出版状态已出版 - 15 11月 2024

指纹

探究 'A fully recrystallized heterogeneous grain structure with dispersed second phases for enhancing strength-ductility synergy in an Al-Cu-Mn alloy' 的科研主题。它们共同构成独一无二的指纹。

引用此