Abstract The 3-D distributions of the micro-defects in the PEO coating on ZM6 Mg-alloy were investigated using X-ray tomography (XRT) and confocal laser scanning microscopy (CLSM) in conjunction with scanning electron microscopy (SEM). The results showed that micro-defects with different sizes and shapes existed in the pristine PEO coating. The sizes, shapes, and numbers of micro-defects of the PEO coating in 3.5 % NaCl solution changed greatly with immersion time under the synergistic effects between corrosion and the extension of corrosion products. Finally, the through-defects were formed by connecting the adjacent micro-defects and the substrate corroded.

中文翻译：

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ZM6镁合金PEO涂层腐蚀过程中微观缺陷的3-D分布特征

摘要 使用 X 射线断层扫描 (XRT) 和激光共聚焦扫描显微镜 (CLSM) 结合扫描电子显微镜 (SEM) 研究了 ZM6 镁合金上 PEO 涂层中微观缺陷的 3-D 分布。结果表明，原始PEO涂层中存在不同大小和形状的微缺陷。在腐蚀和腐蚀产物扩展的协同作用下，PEO涂层在3.5% NaCl溶液中微缺陷的大小、形状和数量随着浸泡时间的变化而发生很大变化。最后，通过连接相邻的微缺陷和腐蚀的基板形成贯通缺陷。