Fe-Al/Al2O3涂层表面氧化膜的掠入射X射线衍射研究

本文采用掠入射X射线衍射（GXRD）α-2θ扫描模式，进行了掠入射角α为0.1°～5°范围内Fe-Al/Al₂O₃阻氚涂层表面氧化膜的X射线衍射实验。结果表明，随α的增加，表面氧化膜中Al₂O₃相与Fe₃Al相对应的衍射峰强度绝对值增强；α的增加加深了分析区域的深度，引起Al₂O₃相的相对含量下降，导致Al₂O₃相对衍射峰强度降低。对Fe-Al/ Al₂O₃涂层表面氧化膜的掠入射X射线衍射而言，较佳的掠入射角是0.25°，此时对应Al₂O₃相的衍射峰相对强度最高。经比对PDF卡片，表面氧化膜相结构为暂态γ-Al₂O₃（200）。在此基础上建立了GXRD分析Fe-Al/ Al₂O₃涂层表面亚微米氧化膜的相结构组成的快速无损检测方法。

Grazing X-ray Diffraction of Surface Oxide Films on Fe-Al/Al2O3 Composite Coating

The α-2θ scanning mode of grazing incident X ray diffraction (GXRD) was employed to study the phase structure of surface oxide films for the Fe-Al/ Al₂O₃ tritium permeation barriers. The incident angles (α) were chosen from 0.1° to 5° in the experiment. After analyzing the GXRD spectra of the surface layer on the Fe-Al/ Al₂O₃ coatings under different incident angles, the results indicate that the total amount of intensity of alumina and Fe₃Al  increases with the enlarge of incident angles. However, the relative intensity of alumina decreases in the same time. The reason is that the penetrable depths of X-ray through the surface layer of the Fe-Al/ Al₂O₃ coating increases with the incident angle. Form the result, the best incident angle for analyzing the oxide films on the Fe-Al/ Al₂O₃ tritium permeation barriers is 0.25°. The main phase structure of the oxide films is γ-Al₂O₃ (200). In conclusion, a rapid and nondestructive testing of phase structure analysis method for the surface oxide films on the Fe-Al/ Al₂O₃ tritium permeation barriers was established in this paper.