An examination of microstructural evolution and homogeneity in a magnesium AZ80 alloy processed by high-pressure torsion

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:806

Article

Zhang, Nian Xian^1,2  Kawasaki, Megumi³  Ding, Hua¹  Langdon, Terence G.^4,5,6 

[1] Northeastern Univ, Sch Mat Sci & Engn, Shenyang 110819, Liaoning, Peoples R China

[2] Crown Technol, Mat Dept, Downsview Rd, Wantage OX12 9BP, England

[3] Oregon State Univ, Sch Mech Ind & Mfg Engn, Corvallis, OR 97331 USA

[4] Univ Southampton, Mat Res Grp, Dept Mech Engn, Southampton SO17 1BJ, Hants, England

[5] Univ Southern Calif, Dept Aerosp & Mech Engn, Los Angeles, CA 90089 USA

[6] Univ Southern Calif, Dept Mat Sci, Los Angeles, CA 90089 USA

关键词: Hardness;    High-pressure torsion;    Homogeneity;    Magnesium alloy;    Shear instabilities;   

DOI  :  10.1016/j.msea.2021.140832

来源: Elsevier

【 摘 要 】

A magnesium AZ80 alloy with an initial grain size of-250 mu m was processed by high-pressure torsion for up to 12 turns at room temperature. The processing produced increased hardness and significant grain refinement with average grain sizes of-320 and-200 nm at the edges of the discs after 1 and 12 turns, respectively. Microstructural examinations on different planes along the thickness direction of the discs revealed the presence of shear bands and twin boundaries and there were significant inhomogeneities even after 12 turns. The results show the presence of well-defined vortices having similarities to the well-established Kelvin-Helmholtz shear instabilities in fluid flow.

【 授权许可】

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