Structural Relaxation and Properties of Planar Defects in Amorphous and Nanocrystalline Metals

该基金探索了非晶和纳米晶金属的物理特性，重点研究了这些材料中剪切带和晶界的弛豫。目的是通过热处理来改变这些缺陷的松弛状态。目标是利用包括高分辨率成像和能量滤波在内的最先进的透射电子显微镜来表征结构变化。这些材料将使用电沉积和球磨技术进行加工。各种性能，如储存焓，稳定性，硬度，应变率敏感性和扩散行为将进行评估。研究结果将有助于对剪切带和纳米晶界的结构、这种结构的修改以及由此产生的性能变化的基本理解。这些将有助于非晶和纳米晶金属结构应用的知识库，如MEMS和NEMS技术。该资助有助于教育和培训研究生在最先进的电子显微镜和结构材料的性质表征。

The grant explores the physical properties of amorphous and nanocrystalline metals with emphasis on the relaxation of shear bands and grain boundaries respectively in these materials. The objective is to modify the relaxation state of these defects by thermal treatment. The goal is to characterize the structural changes using the state-of-the-art transmission electron microscopy including high-resolution imaging and energy filtering. The materials will be processed using electrodeposition and ball milling techniques. Various properties such as the stored enthalpy, stability, hardness, strain-rate sensitivity and diffusion behavior will be evaluated.The results from the grant are expected to contribute to the fundamental understanding of the structure of shear bands and nanograin boundaries, modification of this structure, and the resulting property changes. These will contribute to the knowledge base for structuralapplications of amorphous and nanocrystalline metals such as in MEMS and NEMS technologies. The grant helps to educate and train graduate students in state-of-the-art electron microscopy and property characterization of structural materials.