不均一超微細粒組織を有するマグネシウム合金の変形機構の解明

我们发现，在拉伸试验过程中，脱孪晶发生在一个试样规模的应变局部化带的形成，传播和湮灭。这是AZ 31镁合金中的一个新发现。此外，我们认识到，AZ 31镁合金伴随着去孪晶，表现出微观不均匀变形由于去孪晶和滑移激活也是重要的。为了研究为什么显示出显著去孪晶行为的0 °试样与显示出拉伸性能的一般形状的90 °试样相比显示出如此不同的拉伸性能，需要研究每个试样的变形行为。因此，我们进行了微观DIC分析，以检查滑移和去孪晶对变形的影响。结果发现，不仅0 o试样的应变分布不均匀是由于去孪晶，90 o试样的应变分布也不均匀是由于滑移变形，因此必须考虑每个试样的滑移行为，才能理解哪种滑移变形被激活以及应力-应变曲线为何如此不同。研究了预压缩AZ 31镁合金的哪种滑移系被激活。基底<a>滑移主要在基体和孪生前区激活。我们还需要研究拉伸变形试样的变形结构，以了解&lt;c+a&gt;或棱柱滑移是否被激活。

We found out that de-twinning takes place in a specimen scale with formation, propagation, and annihilation of strain-localized banding during the tensile test. This is a new finding in AZ31 Mg alloy. Furthermore, we realized that AZ31 Mg alloy accompanying de-twinnning shows microscopic inhomogeneous deformation due to de-twinning and slip activation is also important. In order to investigate why the 0o specimen showing significant de-twinning behavior shows such different tensile properties in comparison to the 90o specimen showing the general shape of tensile properties, the deformation behavior of each specimen needs to be investigated. Therefore, we conducted a micro-DIC analysis to examine the effect of slip and de-twin on deformation. As a result, we figured out that not only the strain distribution of the 0o specimen was heterogeneous due to de-twinning, but also the strain distribution of the 90o specimen was inhomogeneous due to the slip deformation.The slip behavior of each specimen must be taken into account to understand what kinds of slip deformation are activated and why the stress-strain curve is so much different. We investigated which kinds of slip systems of a pre-compressed AZ31 alloy were activated. Basal <a> slip was mainly activated in the matrix and pre-twinned region. We still need to investigate the deformation structure of tensile deformed specimens to know whether <c+a> or prismatic slip was activated or not.