Coherent interface strengthening of ultrahigh pressure heat-treated Mg-Li-Y alloys. (15th August 2020)

• Record Type: Journal Article
• Authors: Zhang, Shun; Sun, Yong; Wu, Ruizhi; Wang, Xiang; Chen, Xiao-Bo; Fernandez, Carlos; Peng, Qiuming
• Is Part Of: Journal of materials science & technology. Volume 51(2020)
• Page Start: 79
• Page End: 83
• Publication Date: 2020-08-15
• Subjects: Mg alloys -- Nano-twins -- Stacking faults -- Strengthening; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2020.02.039
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: Achieving good strength-ductility of Mg alloys has always been a crucial issue for the widespread applications of Mg-based structural materials. Herein, an unexpected double-stage strengthening phenomenon was discovered in Mg-8Li-1Y(wt.%) alloys through high pressure (6 GPa) heat treatments over a range of 700-1300 °C. Attractively, the yield strength values are improved remarkably without losing their ductility. The low temperature strengthening mechanism is mainly driven by the formation of large-volume nanoscale contraction twins. In contrast, the high-temperature strengthening reason is ascribed to the presence of densely nano-sized stacking faults. Both coherent interfaces contribute effectively to high mechanical strength without any tradeoff in ductility.