初始织构对高温轧制AZ31镁合金板显微组织与织构影响的EBSD研究

Study of effects of initial texture on the microstructure and texture for hot rolled AZ31 Mg alloy sheet using EBSD

本文采用EBSD方法表征分析了不同初始取向的AZ31镁合金原料板材经300℃热轧69%后得到的终轧产品的显微组织与织构差异,考察了热轧变形条件下原料的初始织构对热轧成品板材的影响。结果表明,原料的初始织构对终轧板材的显微组织与织构影响不大,但对材料的显微组织界面分布有一定影响。通过高温大变形量变形,不同初始织构的原料均可制得平均晶粒度小于5μm的AZ31镁合金板材。

The purpose of this work was to characterize the heavily hot-rolled AZ31 Mg alloy sheets produced from different initial AZ31 Mg alloy plate with different texture using EBSD technique,and analyze the effects of the initial texture on the AZ31 Mg alloy sheet hot-rolled at 300 ℃.The microstructure,texture and grain boundary feature of products were compared and discussed.The results show that the influence of different initial texture is a minor effect on the grain size and texture of rolled AZ31 Mg alloy sheet;however it affects the deformation mechanism during rolling and so to the distribution of grain boundaries of products.A few {1012} tensile twins can be found in the rolled product which has a initial texture with c-axes perpendicular to the compression direction,while the other product which has a initial texture with c-axes parallel to the compression direction are absent of tensile twins.AZ31 Mg alloy sheets with the mean grain size under 5 μm can be obtained through heavily hot rolling to 69% at 300 ℃ from different initial plate which has different texture,and EBSD is found to be a powerful technique for rapid material characterize.