宽温域内具有高强度和连续润滑功能的复合材料的设计、制备及机理研究

In view of wide demands for the lubricating materials with high strength and continuous lubricating properties in advanced aircraft engines, the design, fabcication and mechanisms of solid lubricating materials with continuous lubricating properties and high strength in wide temperature range are investigated. By using the syneregistic strengthening methods of solid solution strengthening of alloying elements, the precipitation strengthening of gamma prime phase and the oxide dispersion strengthening, and the synergistic effects of extrinsic lubricants with the in situ formed lubricants during the tribochemical reation, together with optimizing the processes of preparing and heating treatments, the composites with high strength and continuous lubricating properties of in wide temperature range would be fabricated. The influences and mechanisms of alloying elements, dispersed oxide, lubricants and the processes of preparing and heating treatment on the strength and tribological properties in wide temperature range would be explored. The mechanisms of deformation and fracture, as well as the principles of friction-reducing and antiwear would be clarified. The relation between microstructures, structures and properties of the composites would be elucidated, then the theories of composites with high strength and continuous lubricating properties in wide temperature range would be expounded. Finally, the design principles and the processes of preparing and heating treatments of the composites with high strength and continuous lubricating function in wide temperature range would be confirmed. This project would accumulate the theoretical data and provide the technical support for the development of new composites with high strength and continuous lubricating properties which are urgently demand in the aviation and aerospace fields.

针对先进航空发动机对具有高强度和连续润滑功能的材料的广泛需求，开展固体润滑材料的宽温域连续润滑功能设计和强度设计及相关机理研究。利用合金元素固溶强化、γ′相沉淀强化、氧化物弥散强化的复合强化机制，通过润滑剂复配及摩擦化学反应自生成润滑相的协同，并结合制备及热处理工艺优化，实现材料在宽温域内机械强度和润滑性能的优化统一；探讨合金元素、弥散强化相、润滑剂、摩擦化学反应产物及其之间的交互作用以及制备、热处理工艺对材料宽温域内强度和润滑性能的影响及机理；阐明材料在不同温度下的变形、断裂机制以及减摩抗磨原理；明确材料组织、结构与性能之间的关系，揭示宽温域内材料机械性能和连续润滑功能优化统一的机理；提出宽温域内具有高强度和连续润滑功能的复合材料的设计组配原则，并形成与材料配方体系相适应的关键制备技术。为发展我国航空、航天等战略高技术领域迫切需求的新型高强度连续润滑材料积累基础理论数据和提供技术支持。

本项目针对先进航空发动机对具有高强度和连续润滑功能的材料的广泛需求，开展宽温域内具有高强度和连续润滑功能的复合材料的设计、制备及机理研究。本项目设计制备了金属陶瓷基、Ni基、NiAl金属间化合物基三种体系的复合材料，金属陶瓷基复合材料以Al2O3为强化相，石墨、二硫化钼（MoS2）、Ag、硫酸锶（SrSO4）等为润滑相；Ni基复合材料以Cr、Mo、Al、Ta、弥散强化氧化物（-Al2O3）为强化元素和增强相，Ag、MoS2为润滑相；NiAl金属间化合物基复合材料以Nb（反应生成NbC）为强化相，Ag、AgNbO3为润滑相。考察了复合材料的硬度、密度等物理性能，分析了材料烧结前后、热处理后的显微组织，优化了三种复合材料的制备工艺；考察了复合材料在宽温域内的机械性能（拉伸、压缩），探讨了材料的断裂机制；考察了复合材料在宽温域内的摩擦学性能（摩擦系数、磨损率），阐明了材料在不同温度下的磨损机理，分析了摩擦化学反应对摩擦学性能的影响及机理，研究了强化相、润滑相、摩擦化学反应产物及其之间的交互作用对材料摩擦学性能的影响。后续将重点研究材料的变形、断裂机制，分析强化相、润滑相、摩擦化学反应产物等对位错组态及位错运动规律的影响；揭示宽温域内材料机械性能和摩擦学性能优化统一的机理；并将继续开展长期时效试验，研究长期时效过程中材料的显微组织演化规律及长期时效后材料的机械性能和摩擦学性能，进一步明确材料的组织—结构—性能之间的关系。通过本项目的研究，提出了宽温域内具有高强度和连续润滑功能的复合材料的设计组配原则，并形成了与材料配方体系相适应的关键制备技术，为发展我国航空、航天等战略高技术领域迫切需求的新型高强度连续润滑材料积累了基础理论数据，提供了技术支持。