Enhanced mechanical properties and formability of hot-rolled Mg-Zn-Mn alloy by Ca and Sm alloying
(1. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
2. Ningbo Research Institute of Dalian University of Technology, Ningbo 315016, China)
2. Ningbo Research Institute of Dalian University of Technology, Ningbo 315016, China)
Abstract: In order to broaden the application of wrought Mg alloy sheets in the automotive industry, the influence of Ca and Sm alloying on the texture evolution, mechanical properties, and formability of a hot-rolled Mg-2Zn-0.2Mn alloy was investigated by OM, XRD, SEM, EBSD, tensile tests, and Erichsen test. The results showed that the average grain size and basal texture intensity of Mg-2Zn-0.2Mn alloys were remarkably decreased after Ca and Sm additions. 0.64 wt.% Ca or 0.48 wt.% Sm addition significantly increased the tensile strength, ductility and formability. Moreover, the synergetic addition of Sm and Ca improved the ductility and formability of Mg-2Zn-0.2Mn alloy, which was due to the change of Ca distribution and further reduction of the size of Ca-containing particles by Sm addition. The results provided a possibility of replacing RE elements with Ca and Sm in Mg alloys which bring about outstanding mechanical properties and formability.
Key words: Mg-Zn-Mn alloy; micro-alloying; hot rolling; texture evolution; formability