Cu-4wt%Ti合金有序化X射线与电子衍射谱的计算机模拟

COMPUTER SIMULATION OF X-RAY DIFFRACTION PROFILES AND TEM DIFFRACTION PATTERNS ON ORDERING FOR Cu 4wt%Ti ALLOY 

在点阵波理论基础上 ,通过假定Cu 4wt%Ti合金中溶质原子浓度的适当分布并建立与之相应的衍射波波幅表达式 ,利用计算机模拟得该合金调幅分解与有序化共存时X射线衍射边带形貌 ,其波形与实验结果颇为相近 ;进一步根据波的叠加原理在两相互垂直方向上对上述衍射形貌合成 ,获得Cu 4wt%Ti合金 40 0℃时效较长时间同时出现的D1a型和B2型复杂有序化超点阵斑 ,其强度与位置分布均与透射电镜 (TEM)

On the basis of lattice wave theory, the several side band profiles of X Ray diffraction of spinodal decomposition for Cu 4wt%Ti alloy are simulated by computer through supposing the rectangular distribution of solute atoms in the alloy, and the profiles are extremely similar to experimental results. Moreover, in the light of the principle of superposition, the composition of the above\|mentioned profiles which are perpendicular to each other in two directions is carried out and the simulated diffraction patterns obtained are extremely good consistent with TEM diffraction pattern.