VAlCN纳米复合涂层的设计制备及宽温域低摩擦机理

The lubrication and wear performance over wide temperature ranges of moving parts under extreme harsh conditions in the area of modern aviation, aerospace, nuclear power and other high-tech industries, closely affect the reliability and lifetime of the entire system. Therefore, it is of great significance to research and develop coatings having a low friction and wear resistance which are capable of adaptive contact chemistry and structural evolutions over a wide range of temperature. The coating material which has the potential to operate at a wide range temperature consist of a combination of multi lubricious and double metal oxides lubricious induced by elevated tribo-oxidation. In this study, carbon, Ag, and V was adopted for a synergistic combination of multi lubricious. The fabrication of VAlCN coatings was by means of structure design, multi components lubricious and interface construction. The amount of amorphous carbon, V/Al ratio was mainly controlled aiming to achieve a hard nanocomposite coatings wrapped by amorphous carbon at the grain boundary. The effect of chemical composition, elemental distribution and microstructure characteristics on the high-T diffusion and oxidation of V and Ag will be investigated. The thermal stability and the board-temperature tribological behaviors will be discussed. The adaptive mechanism of self-lubricating VAlCN coatings over wide temperature ranges will be clarified. These results are not only important of insight into the fundamental mechanism of low friction coatings with high performance, but also bring forward a new strategy to develop new lubricants to meet the need for wide temperature range applications.

航空、航天、核电等领域的关键部件在冷启动到最高工作温度的宽温域摩擦磨损问题，严重影响整个系统的运行稳定性和安全可靠性。能够根据温度环境变化，调整摩擦接触化学的自适应低摩擦涂层材料是解决这一问题的关键。而通过多相润滑剂复配和高温摩擦诱导润滑膜协同是实现宽温域低摩擦涂层材料的核心思路。本项目基于非晶碳、Ag、及高温摩擦诱导V2O5 Magnéli相和AgVO4协同复配的设计思路，从VAlCN涂层微观结构、组元特性协同和界面优化三方面入手，重点调控非晶碳、V/Al组分配比，实现纳米复合结构VAlCN涂层的可控制备。通过高温热稳定性/宽温域摩擦行为的研究，明晰润滑相V、Ag高温扩散及氧化的演变规律，阐明宽温域自适应减摩抗磨机制。研究结果不仅可丰富对高性能润滑涂层材料摩擦学基础理论的深入理解，且可为发展设计航空、航天、核电等高技术领域用新一代宽温域低摩擦材料技术提供重要依据。

针对现有航空航天高技术领域用宽温域润滑材料体系不深入，多相复合润滑机理和磨损失效机制不明的挑战，本项目基于硬质基础相、多组分复合润滑相、高温诱导原位自润滑相协同的宽温域环境自适应低摩擦设计思路，开发了兼具高温抗磨与减摩性能VAlN系纳米复合/多层结构涂层及制备技术。明确了涂层物相组分、结构、性能之间的关系；阐明了V、Ag、O元素在宽温域摩擦过程中的扩散机制及摩擦氧化机理，润滑相的演变机制及其对摩擦学行为的影响规律。提出了适用于宽温域润滑的涂层优化设计策略，通过a-C修饰硬质高温润滑涂层表面，改善中低温摩擦学性能；通过基础相、增强相和润滑相复配制备宽温域低摩擦涂层；通过M位固溶提升MAX相涂层的综合性能和摩擦学性能。相关研究为发展宽温域、高温、高速等苛刻环境防护涂层提供理论依据和技术指导。