Connecting Nanoscale Structure and Plasticity in Bulk Metallic Glasses

该奖项的研究目标是将大块金属玻璃（BMG）中的结构与塑性变形联系起来。涨落电子显微镜（FEM）的实验将被用来测量BMG纳米级中程秩序。 有限元数据将结合一个经验的原子间势在一个混合的反向蒙特卡罗结构细化，生产模型与现实的短期和中期结构。 对Pd-Si块体玻璃的研究将为最近提出的Zr-Cu-Al块体玻璃结构模型的通用性提供必要的测试，该模型由具有晶体状和二十面体状内部结构的纳米区域组成。 如果晶体状纳米尺度区域是BMG结构的一般特征，那么它可能对其塑性流动模型产生重大影响。如果成功，这项研究将为BMG合金的扩展应用奠定基础科学基础，通过详细了解其结构及其与塑性的关系，最终帮助设计具有所需机械和玻璃形成特性的新合金。 研究团队将涉及本科生和研究生，特别是来自代表性不足的群体，并将使公众和K-12学生参与研究的兴奋和成果。

The research objective of this award is to connect structure to plastic deformation in bulk metallic glasses (BMGs). Experiments with fluctuation electron microscopy (FEM) will be used to measure nanoscale medium-range order in BMGs. The FEM data will be combined with an empirical interatomic potential in a hybrid Reverse Monte Carlo structural refinement, producing models with realistic short- andmedium-range structure. Research on Pd-Si BMGs will provide an essential test of the generality of a recently proposed structural modelfor Zr-Cu-Al BMGs that consists of nanometer-regions with crystal-like and icosahedral-like internal structure. If crystal-like nanometer scale regions are a general feature of BMG structure, it could have significant impact on models of their plastic flow.If successful, this research will lay the fundamental scientific groundwork for expanded applications of BMG alloys, by eventually assisting design of new alloys with desired mechanical and glass-forming characteristics through detailed understanding of their structure and its connection to plasticity. The research team will involve undergraduate and graduate students, especially from under-represented groups, and will engage the general public and K-12 students in the excitement and outcomes of the research.