Atomic Resolution Studies of Solute-Atom Segregation and Phase Transitions at Internal Interface

用先进的高分辨技术研究了金属合金内部界面的溶质原子偏析和相变。其目的是了解溶质原子的偏析作为界面结构和大块体系热力学的函数。用原子探针场离子显微镜和原子分辨分析电子显微镜测量了各晶界的化学成分。利用模拟技术研究了晶界的八维超空间中溶质原子的偏析和相变。用不同的晶界研究了倾斜晶界和扭曲晶界。%界面性质在决定金属合金的重要性质方面起着重要作用，这些性质可以决定其最终用途，例如结构材料或磁性材料。这项研究应该能更好地理解界面处的溶质偏析，而界面偏析又会影响界面性质。

Solute atom segregation and phase transitions at internal interfaces in metal alloys are studied using sophisticated high resolution techniques. The objective is to understand the segregation of solute atoms as a function of the structure of an interface and the thermodynamics of the bulk system. The chemical compositions of individual boundaries are measured by atom probe field ion microscopy and atomic resolution analytical electron microscopy. Simulation techniques are employed to explore the eight-dimensional hyperspace of a grain boundary with respect to solute atom segregation and phase transitions. Both tilt and twist grain boundaries are studied with different crystallographic interfaces. %%% Interface properties play a major role in determining important properties of metal alloys that can determine their end use, such as a structural material or magnetic material. This research should result in a better understanding of solute segregation at interfaces, which in turn affects the interfacial properties.