Micromechanical Testing and Multivariant Model Correlation for Shape Memory Alloys

9908368 Brinson在这项工作中，形状记忆合金（SMA）的单轴和多轴载荷的响应将研究与扫描电子显微镜和电子背散射衍射。实验将提供详细的信息，在不同的负载条件下的变体的演变，并将比较PI的“多变量”微观力学模型。此外，结果将提供洞察假设的转换应变中使用的塑性为基础的SMA本构模型。这项工作代表了SMA行为尚未被研究的方面的调查：虽然材料科学界已经处理了马氏体变体结构的识别，力学界已经处理了宏观建模，但还没有研究过直接了解在施加载荷下形成的变体以及在不同载荷条件下如何转化为宏观应变。然而，这些问题必须得到理解，使SMA的研究和应用取得重大进展。

9908368BrinsonIn the work, shape memory alloy (SMA) response to uniaxial and multiaxial loading will be studied with Scanning Electron Microscopy and Electron BackScattered Diffraction. The experiments will provide detailed information on the evolution of variants under different loading conditions and will be compared to the PIs "multivariant" micromechanics model. In addition, results will give insight into the assumptions for transformation strains used in plasticity-based SMA constitutive models. The work represents investigation of aspects of SMA behavior that have not yet been examined: while the materials science community has dealt with identification of martensitic variant structure, and the mechanics community has dealt with macroscale modeling, a direct understanding of exactly which variants form under applied load and precisely how that translates into macroscopic strain for different loading conditions has not been studied. Yet these issues must be understood to make significant progress in SMA research and applications.