中文摘要：

采用小型微弧氧化电源装置和新颖的喷射式阴极，解决传统的浸入式微弧氧化工艺不能用于外场大面积构件局部修复用涂层制备的问题。采用XRD、SEM、EDS等分析手段研究涂层的物相与组织结构。用动电位极化法及盐雾腐蚀试验评价涂层的抗腐蚀性能。结果表明，相同电参数条件下，喷射式微弧氧化电流密度略高于浸入式氧化，生长的涂层厚度稍低于浸入式氧化，喷射式与浸入式微弧氧化涂层生长规律一致。涂层主要由α-Al2O3和γ-Al2O3组成，涂层内层致密，表面多微孔。TAFEL极化曲线与盐雾腐蚀测试均表明，微弧氧化涂层明显改善LY12铝合金抗腐蚀性能。

英文摘要：

The spraying microarc oxidation process with a small scale pulsating source was used as field repairing purpose to prepare ceramic coatings in the local damaged region on large size aluminium component instead of the immersing microarc oxidation method. Microstructure and phase composition of coatings were characterized by SEM, XRD and EDS. The corrosion resistance properties of coatings were determined by potentiodynamic polarization and salt spraying test. The results show that under the same applied electrical parameters, the current density during spraying microarc oxidation is slightly higher than that of immersing oxidation, while the coating thickness is lower compared with immersing oxidation. The coating growth shows a similar variation in both oxidation modes. The coating, mainly composed of α-Al2 O3 and γ-Al2O3, is dense in the inner layer, porous in the outer layer. The potentiodynamic polarization and salt spraying test indicates the microarc oxidation coating obviously improves the corrosion properties of LY12 alloy.