In this study, Al₂O₃ and Al₂O₃–Ca₂SiO₄ coatings were deposited by atmospheric plasma spraying technique. Immersion experiments were performed in deionized water for 1 day and 10 days. The composition and microstructure evolutions of pure and composite coatings with immersion time were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS). Microhardness, roughness and insulation resistance of as-sprayed and immersed coatings were evaluated. In particular, a temperature of ~25 °C and various humidity levels (~10% RH, ~42% RH, ambient humidity and ~95% RH) were applied in the test of electrical resistance. Relationships between mechanical and electrical properties with coating characteristics were discussed. It is shown that the introducing of Ca₂SiO₄ in Al₂O₃ coatings can improve the electrical resistivity under low, middle and ambient humidities, especially after 1 day of immersion. Taking into account the insulation resistance values and mechanical properties of the considered coatings, the plasma sprayed Al₂O₃–5 wt% Ca₂SiO₄ is perhaps a promising material for industrial applications.

在本研究中，Al ₂ O ₃和 Al ₂ O ₃ –Ca ₂ SiO ₄涂层是通过大气等离子喷涂技术沉积的。浸泡实验在去离子水中进行 1 天和 10 天。通过 X 射线衍射 (XRD)、扫描电子显微镜 (SEM) 和能谱仪 (EDS) 研究纯涂层和复合涂层的成分和微观结构随浸泡时间的变化。评估了喷涂和浸渍涂层的显微硬度、粗糙度和绝缘电阻。特别是，在电阻测试中应用了~25°C 的温度和各种湿度水平（~10% RH、~42% RH、环境湿度和~95% RH）。讨论了机械和电气性能与涂层特性之间的关系。结果表明，在Al中引入Ca ₂ SiO ₄₂ O ₃涂层可以提高低、中和环境湿度下的电阻率，尤其是浸泡1天后。考虑到所考虑涂层的绝缘电阻值和机械性能，等离子喷涂的 Al ₂ O ₃ –5 wt% Ca ₂ SiO ₄可能是一种有前途的工业应用材料。