Change of deformation mechanisms in ultrafine grained Mg-Zn-Zr-Ca alloy

7th International Conference on Nanomaterials by Severe Plastic Deformation

Zheng, Ruixiao^1 ; Bhattacharjee, Tilak^1,2 ; Shibata, Akinobu^1,2 ; Sasaki, Taisuke^3 ; Hono, Kazuhiro^3 ; Tsuji, Nobuhiro^1,2

Department of Materials Science and Engineering, Kyoto University, Yoshida Honmachi, Sakyo-ku, Kyoto

606-8501, Japan^1

Elements Strategy Initiative for Structural Materials (ESISM), Kyoto University, Japan^2

National Institute for Materials Science, 1-2-1 Sengen, Tsukuba

305-0047, Japan^3

关键词: Deformation mechanism;    Deformation microstructure;    Deformation twinning;    Dominant deformation mechanism;    High pressure torsions;    Non-basal slip systems;    Strength and ductilities;    Ultra-fine grained ( UFG);   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/194/1/012016/pdf
DOI  :  10.1088/1757-899X/194/1/012016

来源: IOP

【 摘 要 】

In this study, a fully recrystallized ultrafine grained (UFG) Mg-Zn-Zr-Ca alloy was successfully fabricated by a process including high pressure torsion (HPT) and subsequent rapid annealing. Room temperature tensile test revealed that the UFG Mg alloy with a mean grain size of 0.98 μm exhibited simultaneously enhanced strength and ductility compared to those of the coarse grained counterpart (grain size 57 μm). Observation of deformation microstructures revealed that {10-12} deformation twinning and basal slip were the dominant deformation mechanisms in the coarse grained specimen, while deformation twinning was significantly inhibited but non-basal slip systems seemed activated in the UFG specimen. The reason for the enhanced mechanical properties in the UFG specimen was discussed based on the change of deformation mechanisms observed.