论文部分内容阅读
有序材料的一些特殊的结构参数与性能有着直接的联系。本工作主要叙述利用分析电子显微术的方法作有序材料中局域化的有序度测定;合金化元素占据主元素点阵位置占有率的测定及各向异性的电势分布测定。1.局域化的有序度测定本工作介绍两种方法,并以实例说明。其一是采用透射电子显微镜微衍射的方法。其原理是有序结构在衍射谱上的主要标志是超结构线,超结构线强度与基体衍射线强度之比值的变化反映了有序度的变化。以IC—218合金为例,200kV加速电压,电子束斑直径6nm,试样厚度为100nm,发现该试样中小角晶界附近存在一个约20nm的无序区。
Some special structural parameters of ordered materials are directly related to their properties. This work mainly describes the use of analytical electron microscopy for the orderly determination of the ordered materials; the alloying elements occupy the position of the main element lattice occupancy and anisotropy potential distribution determination. 1. Localization of the degree of determination This work describes two methods, and an example. One is the use of transmission electron microscopy micro-diffraction method. The principle is that ordered structure in the diffraction spectrum is the main symbol of the super-structure line, super-structure line intensity and matrix diffraction line intensity ratio changes reflect the degree of order. Taking IC-218 alloy as an example, an accelerating voltage of 200 kV, an electron beam spot diameter of 6 nm and a sample thickness of 100 nm, a disorder zone of about 20 nm exists near the small-angle grain boundaries in the sample.