Local Atomic Arrangements in Alloys and Intermetallics

本研究的目的是考察几种呈现亚稳态过渡态的金属合金系统的局域原子有序性。研究了铝-铜-镁、铁-铍和镍-铍合金中均匀析出的早期阶段。为了更好地理解有序析出物的形成，对镍铝合金中的析出物进行了研究。正在确定淬火后立即出现的铁质马氏体的结构；也在寻求回火后的结构变化。正在使用同步加速器反常色散技术来确定汞-镉-碲化物中的局部原子顺序。先进的X射线衍射法是表征合金体系的主要实验手段。先进的原子位移漫反射X射线散射技术和相关分析是研究的一部分。

The purpose of this research is to examine local atomic order in several metallic alloy systems that display a metastable transitional state. Early stages of homogeneous precipitation is examined in aluminum-copper-magnesium, iron-beryllium and nickel-beryllium alloys. Precipitation from nickel-aluminum alloys is studied to better understand formation of ordered precipitates. The structure of ferrous martensites immediately following the quench is being determined; structural changes from tempering is also pursued. Local atomic order in mercury- cadmium-telluride is being determined using synchrotron anomalous dispersion techniques. Advanced X-ray diffraction methods are the primary experimental tool used to characterize the alloy systems. Advanced diffuse X-ray scattering techniques from atomic displacements and the associated analysis are part of the research.