Obtaining Ultra-High Strength and Ductility in a Mg–Gd–Er–Zn–Zr Alloy via Extrusion,Pre-deformation and Two-Stage Aging
来源期刊：Acta Metallurgica Sinica2021年第1期
论文作者：Lin-Yue Jia Wen-Bo Du Jin-Long Fu Zhao-Hui Wang Ke Liu Shu-Bo Li Xian Du
文章页码：39 - 44
摘 要：The Mg–12Gd–1Er–1Zn–0.9 Zr（wt%） alloy with ultra-high strength and ductility was developed via hot extrusion combined with pre-deformation and two-stage aging treatment.The age-hardening behavior and microstructure evolution were investigated.Pre-deformation introduced a large number of dislocations,resulting in strain hardening and higher precipitation strengthening in the subsequent two-stage aging.As a result,the alloy showed a superior strength–ductility balance with a yield strength of 506 MPa,an ultimate tensile strength of 549 MPa and an elongation of 8.2% at room temperature.The finer and denser β’ precipitates significantly enhanced the strength,and the bimodal structure,small β-Mg5RE phase as well as dense γ’ precipitates ensured the good ductility of the alloy.It is suggested that the combination of pre-deformation and two-stage aging treatment is an eff ective method to further improve the mechanical properties of wrought Mg alloys.
Lin-Yue Jia，Wen-Bo Du，Jin-Long Fu，Zhao-Hui Wang，Ke Liu，Shu-Bo Li，Xian Du
College of Materials Science and Engineering,Beijing University of Technology
摘 要：The Mg–12Gd–1Er–1Zn–0.9 Zr（wt%） alloy with ultra-high strength and ductility was developed via hot extrusion combined with pre-deformation and two-stage aging treatment.The age-hardening behavior and microstructure evolution were investigated.Pre-deformation introduced a large number of dislocations,resulting in strain hardening and higher precipitation strengthening in the subsequent two-stage aging.As a result,the alloy showed a superior strength–ductility balance with a yield strength of 506 MPa,an ultimate tensile strength of 549 MPa and an elongation of 8.2% at room temperature.The finer and denser β’ precipitates significantly enhanced the strength,and the bimodal structure,small β-Mg5RE phase as well as dense γ’ precipitates ensured the good ductility of the alloy.It is suggested that the combination of pre-deformation and two-stage aging treatment is an eff ective method to further improve the mechanical properties of wrought Mg alloys.
关键词：
