中文摘要：

以常规和纳米团聚体ZrO2-7wt%Y2O3复合陶瓷粉末为材料,采用等离子喷涂工艺在TC4钛合金表面制备了常规和纳米结构陶瓷涂层,并对其进行冲蚀实验,研究了涂层微观组织和性能对涂层抗冲蚀性能的影响,以及不同工艺参数下涂层冲蚀性能。用扫描电镜（SEM）和XRD分析了涂层组分和微观结构,同时利用显微硬度计对涂层的硬度进行了测试。结果表明,等离子喷涂纳米ZrO2涂层抗冲蚀性能明显高于常规ZrO2涂层。当冲蚀角为90°时冲蚀失重最大,表现为脆性冲蚀,随着速度的增大冲蚀失重也随之增加。等离子喷涂纳米ZrO2涂层由熔化区和部分熔化区组成,部分熔化区属微纳米结构,熔化区在沉积急冷和冲击应力的作用下会形成细晶,微纳米结构与细晶共同作用下的纳米陶瓷涂层的平均粒度将远远小于常规陶瓷涂层的平均粒度,使其硬度增加;微纳米区域在涂层中其局部晶界的强度特别高,裂纹难以沿着晶界扩展,起到了良好的增韧的作用,硬度和韧性的提高使涂层的抗冲蚀性能增强。

英文摘要：

The conventional and nanosturctured ZrO2-7 wt% Y2O3 composite ceramic coatings were prepared by plasma spraying with conventional powders and agglomerated nano-powders on TC4 alloy surface.Microstructure and properties of the coatings were examined by means of XRD,SEM and hardness tests.The erosion wear behavior of the nano-ZrO2 coatings was investigated by erosion experiment using different erosion parameters.The results show that the erosion resistance of the plasma-sprayed ZrO2 nano-coating is significantly higher than that of conventional ZrO2 coating.The maximum value of weightless of erosion is observed when the erosion angle is 90°,and brittle erosion prevails.The weight loss increases with the increase of erosion velocity.Plasma-sprayed ZrO2 nano-coating is composed of fully melted regions and partially melted regions,and the micro-nanostructure is found in the partially melted regions,and the fine-grain is formed in the fully melted regions under the action of rapid cooling and impact stress during deposition.The average grain size of nano-ceramic coating is much smaller than that of conventional ceramic coating,which increases its hardness;The grain boundary of micro-nanosturctured regions has particularly high strength,preventing cracks growing along grain boundary and toughening the coating.The erosion wear resistance of the nano-ZrO2 coating is significantly improved due to the increase of its hardness and toughness.