晶间变形行为对AZ31镁合金延展性的影响

Effect of intergranular deformation behavior on ductility of AZ31 magnesium alloy

利用拉伸试验结合电子背散射衍射技术研究了AZ31镁合金在不同加载方式下的晶间变形行为,并通过Matlab软件计算了不同晶间变形行为之间Schmid因子、几何相容性因子m’值以及晶间变形相容性mk值,诠释了晶间变形行为对镁合金整体塑性的影响,并与试验结果进行了对比。结果表明,晶界附近的应变调节受相邻晶粒的Schmid因子、几何相容性因子m’值以及晶间变形相容性mk值的影响。晶间变形行为的优先级主要影响晶粒的Schmid因子,对m’值和mk值影响不大。在晶界周围区域,mk值与伸长率是单调递增的关系,相邻晶粒中B-B行为较高的mk值在拉伸试验中表现出更高的伸长率。

The intergranular deformation behaviors of AZ31 magnesium alloy under different loading modes were studied by tensile test combined with electron backscattering diffraction(EBSD)technique.Through the Matlab software,the Schmid factor of adjacent grains,the geometric compatibility factor m’value and the intergranular deformation compatibility mkvalue were calculated.The effects of intergranular deformation beharior on whole plasticity of magnesium alloys were interpreted,and the calculated results were compared with the test results.The results show that the strain regulation near grain boundary is influenced by the Schmid factor of adjacent grains,the geometric compatibility factor m’value and the intergranular deformation compatibility mkvalue.The priority of intergranular deformation behavior mainly affects the Schmid factor of grains,but has little influence on m’value and mkvalue.In the region around the grain boundary,there is monotonically increasing relationship between mkvalue and elongation,and the mkvalues with higher B-B behavior in adjacent grains show higher elongation in tensile test.