Influence of microstructure uniformity on fracture behavior of magnesium alloy rolling sheet based on slip trace analysis  

基于滑移迹线分析的镁合金轧板组织均匀性对断裂行为的影响

作　　者：Jing TIAN Jia-fei DENG Wei LIANG Xi ZHAO Xiao-gang WANG 田静;邓嘉飞;梁伟;赵熹;王小刚(中北大学航空宇航学院,太原030051;太原理工大学分析测试中心,太原030024;太原理工大学材料科学与工程学院,太原030024;太原理工大学先进镁基材料山西省重点实验室,太原030024;山西银光华盛镁业股份有限公司,闻喜043800)

机构地区：[1]School of Aerospace Engineering,North University of China,Taiyuan 030051,China [2]Instrumental Analysis Center,Taiyuan University of Technology,Taiyuan 030024,China [3]College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China [4]Shanxi Key Laboratory of Advanced Magnesium-based Materials,Taiyuan University of Technology,Taiyuan 030024,China [5]Shanxi Yinguang Huasheng Magnesium Co.,Ltd.,Wenxi 043800,China

出　　处：《Transactions of Nonferrous Metals Society of China》2025年第4期1122-1136,共15页中国有色金属学报(英文版)

基　　金：supported by the National Natural Science Foundation of China(No.U1810208);Shanxi Province Science and Technology Major Projects,China(No.2018110100)。

摘　　要：The nonuniform microstructure of magnesium alloy rolled sheets tends to influence their plastic deformation capacity.This study employed multi-pass restricted rolling to successfully prepare AZ31 magnesium alloy rolled sheets with a uniform microstructure,enhancing their mechanical properties.Quasi-in-situ tensile EBSD was used to investigate the effect of microstructure uniformity on the plastic deformation and fracture behavior of magnesium alloy.The results demonstrate that the nonuniformity of the magnesium alloy microstructure intensifies the strain asynchrony between adjacent grains,leading to relative misalignment and crack formation.Fine grains cannot coordinate the strain within their adjacent coarse grains,resulting in ledge formation at their common grain boundaries.Moreover,low-angle grain boundaries(LAGB)influence fracture behavior,rendering fine grains penetrated by LAGB more susceptible to becoming strain concentration areas that promote intergranular fracture and even transgranular fracture.镁合金轧板组织的不均匀性往往影响其塑性变形能力。采用多道次限制轧制的方法成功制备了组织均匀的AZ31镁合金轧板,提高了板材的力学性能。采用准原位拉伸EBSD方法研究了组织均匀性对镁合金塑性变形和断裂行为的影响。结果表明,镁合金组织的不均匀性会加剧相邻晶粒之间的应变异步性,产生相对错位并发展为裂纹。细晶不足以协调其相邻粗晶粒内的应变,导致粗晶粒在其共同晶界处产生晶阶。此外,低角度晶界也会影响断裂行为,低角度晶界穿透的小晶粒更容易成为引起晶间断裂的应变集中区,甚至导致穿晶断裂。

关 键 词：AZ31 magnesium alloy ROLLING MICROSTRUCTURE fracture behavior plastic deformation 

分 类 号：TG146.22[一般工业技术—材料科学与工程]