Enhanced mechanical properties and rolling formability of fine-grained Mg–Gd–Zn–Zr alloy produced by equal-channel angular pressing

• Published in: Journal of alloys and compounds Vol. 643; pp. 28 - 33
• Main Authors: Lu, Fumin, Ma, Aibin, Jiang, Jinghua, Chen, Jing, Song, Dan, Yuan, Yuchun, Chen, Jianqing, Yang, Donghui
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-09-2015
• Subjects: Elongation; Equal channel angular pressing; Equal-channel angular pressing (ECAP); Formability; Grain refinement; Magnesium base alloys; Mechanical properties; Mechanical property; Mg–Gd–Zn–Zr-alloy; Rolling; Stacking; Tensile strength; Yield strength; Rolling; Equal-channel angular pressing (ECAP); Mg–Gd–Zn–Zr-alloy; Mechanical property; Grain refinement
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2015.04.118

•Microstructure refinement and homogeneity of the Mg alloy with LPSO phase were attained after SS plus ECAP.•The refined microstructure resulted in higher strength and better ductility.•The fine-grained alloy was easily rolled into a thin sheet without edge cracking and with high productivity.•The combination processing has a great potential in producing Mg alloys with excellent overall performance.
A fine-grained Mg–1.8Gd–1Zn–0.1Zr (at.%) alloy with long-period stacking ordered (LPSO) phase was obtained via solid-solution(SS) treatment plus multi-pass equal-channel angular pressing(ECAP). The effects of post-ECAP rolling on microstructure change and deformation characteristic of the Mg alloy were investigated. The results showed that the fine-grained alloy after 16 ECAP passes at 658K had a yield strength of 334.4MPa with an elongation of 22.5%. Grain refinement with LPSO formation simultaneously improved the strength and ductility of the ECAPed alloy, indicating a good plastic formability. The ECAPed Mg sheet was easily rolled at 773K from 1.5mm to 0.24mm in thickness without edge cracking. After rolling, the fine-grained Mg alloy exhibited higher tensile strength with appropriate elongation. The post-ECAP rolling has been successfully used in the high productivity of Mg thin sheet with good mechanical properties.