AZ31B镁合金挤压板材单向拉伸的取向演变研究

文章利用SEM/EBSD技术,研究了室温下镁合金挤压板材AZ31B单向拉伸时发生的晶粒取向旋转。根据实验结果和Sachs晶体塑性模型计算结果,详细分析了晶粒基体的拉伸轴向旋转变化规律和滑移系的开动机制,并分析了拉伸孪晶量的影响因素。结果表明,交滑移系的开动可以解释晶粒拉伸轴的变化规律;初始取向不同的晶粒表现出明显不同孪生行为;拉伸孪生量与拉伸孪生的Schmid因子值,以及晶粒拉伸轴和其c轴间的角度密切相关。

An experimental study on grain orientation evolution of Mg alloy extruded sheet AZ31B during uniaxial tensile deformation

The orientation rotation in extruded Mg alloy AZ31B sheets during uniaxial tension deformation at room temperature has been investigated using SEM/EBSD technique.According to the experimental results and the calculated results of Sachs crystal model,the quantitative law of the tensile axis rotation for the grains(parent),and the associated slip systems have been analyzed in detail.The influencing factors of twinning area fraction also have been studied.The results show that the rule of tensile axis rotation can be explained by cross slip systems;the grains with different initial orientations exhibit different twinning behaviors;the area fractions of extensive twins have a close relationship with Schmid factors of extensive twinning and the angle between c-axis and tensile axis of the grains.