AZ31镁合金压缩变形微观织构演变规律

Microtexture Evolvement of AZ31 Magnesium Alloy during Compressing

采用电子背散射衍射(EBSD)原位跟踪实验方法研究了AZ31镁合金压缩变形微观织构演变规律。在温度为170℃条件下,研究了AZ31镁合金轧制板材经过3次连续真空压缩(变形量分别为11%、17%和23%)时,其相同观察区域的微观织构演变。研究结果表明,AZ31镁合金轧制板材的微观织构为典型的(0001)基面织构。当温度为170℃、变形量为11%时,晶粒取向发生显著改变,大部分晶粒都发生了完全孪生,只有少数发生部分孪生,原始的基面轧制织构大幅减弱,孪生变体符合60°/<1010>和86.3°/<1210>取向关系。随着变形量的增加,滑移开始启动,孪晶晶界减少,织构变化不明显。压缩变形过程微观织构演变机理主要以拉伸孪生为主,基本上没有压缩孪生出现。

The microtexture of AZ31 magnesium alloy with compression deformation was studied by electron backscatter diffraction （EBSD） in situ tracking. The microtexture evolvement of the same observation areas of the alloy sheets which were compressed three times continually （deformation of 11%, 17% and 23%, respectively） were investigated. The results show that the microtexture of as-rolled AZ31 magnesium alloy is typical （0001） basic texture. With deformation of 11% and the temperature of 170 ℃, the grain orientation changes remarkably, most grains have been twined fully and a few grains twined partially. The initial basic rolled texture is weakened a lot, and twined grains tropism accord with 60°/ and 86.3°/ orientation. With the increasing of deformation, sliding is start-up, twined boundary decreases and variation of microtexture is not obvious. In compression deformation of AZ31 magnesium alloy, the evolution mechanism of microtexture is the tension twinning, without compression twinning.