高温扩散自补偿润滑轴承的机制及其摩擦学设计基础研究

The project aims to investigate the technology and method for fabrication of high temperature diffusion self-compensation lubricating metal-ceramic bearings, where excellent intensity and toughness, as well as good high temperature self lubrication properties are required. It was fabricated by forming an orderly microporous preform and infiltrating the preform with molten solid lubricant in a vacuum mutative-pressure infiltration furnace. The main contents of the researches include: Using the dimension of spherule pores, arranging direction of cystiform particles and thickness of cystiform particles wall as design variables, the model of micropore preform with a cystiform structure was established. The relationship between design variables and mechanical properties was studied via SIMP interpolation method. The control mechanism of characteristic parameters of micropores was clarified. Based on the dyanmics analysis of infiltration process, the dynamic equations of melt solid lubricants infiltrating micropore preforms under vacuum mutative-pressure condition were set up. The mechanisms and friction and lubrication design foundations of high temperature diffusion self-compensation lubricating bearings were investigated, respectly. Through a combination of theoretical analysis and model test method, the relationship among mechanical properties, friction and wear properties and micro structures of high temperature diffusion self-compensation lubricating metal ceramics was studied systematically. It is of a great significance to the research and development of high temperature diffusion self-compensation lubricating bearings.

针对高温自润滑复合材料轴承强韧性与自润滑性能相互制约的矛盾，拟采用高温真空变压力熔渗复合技术，实现熔融复合固体润滑剂与胞体结构微孔预制体的熔渗复合，获得强韧性与自润滑性能有机统一的高温扩散自补偿润滑金属陶瓷；提出以嵌入到圆柱形实体中的小球形孔尺寸、胞元排列方向及其胞壁厚度为设计变量的胞体结构微孔预制体的设计方法，并建立其微结构模型；由SIMP插值法建立设计变量与力学性能之间的关系，结合造孔剂的联合造孔机制和烧结工艺优化机制，阐明孔结构特征参数的控制机理；通过熔渗过程的动力学分析，建立真空变压力熔渗技术实现熔融固体润滑剂与微孔预制体熔渗复合的动力学关系，揭示高温扩散自补偿润滑轴承的机制；采用理论和试验相结合的方法，系统研究高温扩散自补偿润滑金属陶瓷的力学性能、摩擦磨损性能与材料微结构之间的关系，探索其高温摩擦润滑设计的理论和方法，为设计开发新型高温扩散自补偿润滑轴承提供理论依据和实验指导。

强韧性与自润滑性能的有机统一是解决高温自润滑复合材料轴承强韧性与自润滑性能相互制约矛盾的关键。基于粉末冶金微孔材料微结构的离散性，面向通孔、闭孔的数理统计计算方法，建立了胞体结构微孔预制体的统计数学模型，探讨了微孔结构特征参数的控制机理；分析了材料的微观孔隙结构、组分材料的体分比以及体胞尺度大小与材料的宏观机械性能之间的关系；综合了材料微观结构、组分材料体分比和宏观性能一体化设计的理论和方法；研究了互传网络结构高温自润滑复合材料熔渗复合的动力学条件和热力学条件，建立了高温真空压力熔渗过程的动力学模型；基于各类软金属高温固体润滑剂的润滑特性及其作用机理，分析了复合固体润滑剂的体分比对其润湿微孔预制体的影响规律，建立了与互传网络微孔预制体相匹配，便于扩散析出的复合固体润滑剂的组合设计机制。采用高温真空压力熔渗技术实现互传网络结构微孔预制体的熔渗复合，制备出互传网络结构的高温自润滑复合材料；系统研究了互传网络结构高温自润滑复合材料的力学性能、摩擦磨损性能与材料微结构之间的关系，归纳出高温扩散自补偿润滑轴承的摩擦润滑设计的理论和方法，为设计开发强韧性与高温自润滑性能有机统一的新型高温自润滑复合材料轴承提供理论依据和实验指导。