化学气相沉积钽涂层表面膜层生长动力学机制及耐蚀性能研究

难熔金属钽涂层已经成为我国航空、航天、海洋及新能源领域实现跨越式发展的关键耐腐蚀材料之一。钽涂层的耐腐蚀性能强烈依赖于晶粒取向和表面物理化学特性。然而，该涂层存在严重的选择性腐蚀，制约了其在相关领域的推广和应用。本项目基于缺陷工程的表面热动力学调控理论，提出一种等离子刻蚀表面调控钽涂层耐腐蚀性能的方法。通过热力学解析和分子动力学模拟，明确化学气相沉积(CVD)Ta涂层的沉积行为；采用第一性原理计算，阐明涂层的晶粒取向对表面活性的影响规律。通过实验研究，获得等离子刻蚀参数对CVD;Ta涂层的精细结构、表面状态与耐蚀性的内在作用机制。最终，结合理论计算和实验结果，确定涂层的结构特性、电化学特性和原子位置交互输运过程，构建表面多层结构模型，揭示CVDTa涂层表面微观结构的热动力学缺陷调控机制。本研究可为高性能CVDTa涂层的可控制备提供技术及理论支撑。

Tantalum coating has become one of the key corrosion-resistant materials in the field of aviation, aerospace, ocean and new energy. The corrosion resistance of the tantalum coating strongly depends on grain orientation and surface physical and chemical properties. However, the coating has serious selective corrosion, which restricts its application in related fields. Based on the theory of surface thermokinetic control of defect engineering, this project proposes a method to control the corrosion resistance of tantalum coating by plasma etching. Through thermodynamic analysis and molecular dynamics simulation to determine the deposition behavior of CVD Ta coating; by using the first-principles calculations to clarify the effect of grain orientation on the surface activity of the coating. The intrinsic mechanism of plasma etching parameters on the fine structure, surface state and corrosion resistance of CVD Ta coatings was obtained through experimental study. Finally, combined with the theoretical calculation and experimental results, the structural characteristics, electrochemical characteristics and atomic position interaction transport process of the coating are determined, and the surface multi-layer structure model is constructed to reveal the thermodynamic defect control mechanism of the surface microstructure of CVD Ta coating. This study can provide technical and theoretical support for controllable preparation of high performance CVD Ta coating.