Strong strain path dependence of strain localizations and fracture in magnesium AZ31 sheet  

作　　者：Kivanc Alkan O.Berk Aytuna Baran Guler Mert Efe 

机构地区：[1]Department of Metallurgical and Materials Engineering,Middle East Technical University,Ankara 06800,Turkey

出　　处：《Journal of Magnesium and Alloys》2020年第2期472-479,共8页镁合金学报（英文）

基　　金：This work was supported by European Commission's Research Executive Agency's Marie Sklodowska-Curie Actions-Career Integration Grant(FP7-PEOPLE-2013-CIG)with grant agreement #631774.

摘　　要：This study compares the deformation and fracture behavior of a basal-textured Mg AZ31 alloy sheet under uniaxial tension and biaxial stretching by using an in-plane biaxial test setup capable of observing and measuring the deformation at both meso(millimeter)and microstructure scales.Strain distributions at the mesoscale and accompanying fracture surfaces indicate a significant dependence on strain path.At the microscale,limited slip activity in biaxial case promotes contraction twins,where severe strain localizations(εmax/εmean≈220)to the twins and their boundaries cause mainly transgranular fracture.This leads to a brittle,and a more pronounced shear-type fracture under biaxial stretching.In uniaxial case,considerable tensile twinning activity reorients the initial texture for slip activity.Strain localizations(εmax/εmean≈2)to the grain interiors and boundaries initiate mainly intergranular fracture.Samples fail by displaying both brittle and ductile fracture structures,with smaller shear lips compared to the biaxial case.

关 键 词：FORMABILITY TWINNING BIAXIAL DIC AZ31 

分 类 号：TG146.22[一般工业技术—材料科学与工程]