Tailoring bimodal grain structure of Mg-9Al-1Zn alloy for strength-ductility synergy:Co-regulating effect from coarse Al_(2)Y and submicron Mg_(17)Al_(12) particles  

作　　者：Yong-Kang Li Min Zha Hai-Long Jia Si-Qing Wang Hongmin Zhang Xiao Ma Teng Tian Pinkui Ma Hui-Yuan Wang 

机构地区：[1]State Key Laboratory of Superhard Materials,Jilin University,Changchun 130012,China [2]Key Laboratory of Automobile Materials of Ministry of Education and School of Materials Science and Engineering,Nanling Campus,Jilin University,No.5988 Renmin Street,Changchun 130025,China [3]International Center of Future Science,Jilin University,Changchun 130012,China

出　　处：《Journal of Magnesium and Alloys》2021年第5期1571-1582,共12页镁合金学报（英文）

基　　金：primarily supported by The Natural Science Foundation of China under Grant Nos.51922048,51871108,51625402 and 51671093;Partial financial support came from the Fundamental Research Funds for the Central Universities,JLU,Program for JLU Science and Technology Innovative Research Team(JLUSTIRT,2017TD-09);The Changjiang Scholars Program(T2017035)。

摘　　要：Grain boundary strengthening is an effective strategy for increasing mechanical properties of Mg alloys.However,this method offers limited strengthening in bimodal grain-structured Mg alloys due to the difficultly in increasing the volume fraction of fine grains while keeping a small grain size.Herein,we show that the volume fraction of fine grains(FGs,~2.5μm)in the bimodal grain structure can be tailored from~30 vol.%in Mg-9 Al-1 Zn(AZ91)to~52 vol.%in AZ91-1Y(wt.%)processed by hard plate rolling(HPR).Moreover,a superior combination of a high ultimate tensile strength(~405 MPa)and decent uniform elongation(~9%)is achieved in present AZ91-1Y alloy.It reveals that a desired bimodal grain structure can be tailored by the co-regulating effect from coarse Al_(2)Y particles resulting in inhomogeneous recrystallization,and dispersed submicron Mg_(17)Al_(12)particles depressing the growth of recrystallized grains.The findings offer a valuable insight in tailoring bimodal grain-structured Mg alloys for optimized strength and ductility.

关 键 词：Magnesium alloys Bimodal grain structure Second-phase particles Recrystallization STRENGTH DUCTILITY 

分 类 号：TG146.22[一般工业技术—材料科学与工程]