高强固-液仿生胞局域润滑效应及其控制机理研究

Solid-liquid bionic cellular structures which are composed of a high strength porous matrix and lubricating liquid belong to double phase composite lubricant, while its structures are innovated from biological articular cartilage, and have been expanded to oil complex enhanced by fibres or particles elements, which solve the lubricant self compensation problems of friction pair under the extreme condition effectively. However, such the porous surface has obvious local lubrication characteristics, which affect the continuity of macro lubricating film, and its lubrication controllability still perplex engineering field..In the project, a new concept of local lubrication is proposed based on the double phase elastomer properties and porous surface morphological characteristics of the high strength solid-liquid bionic cellular structures, with the purpose to study the coupling mechanisms between its constitutive characteristics, contact deformation and lubrication state, as well as to reveal the interaction theory between local lubrication and macro lubrication, and to explore its lubrication control strategy. The contents as following will be studied: (1) The multi-scale characterization model and macro contact mechanics performance of bionic double phase composite lubricant; (2) The interaction mechanisms between the local lubrication effect and continuity of macro lubricating film; (3) The local failure mechanism of high strength solid-liquid bionic cellular lubricant and its operational conditions adaptability; (4) The controllability of local lubrication and mutual coupling theory of cellular structure reconstruction..The study results can provide theoretical foundations for the structure design of solid-liquid bionic cellular and life prediction as well as reliability analysis of high strength oil bearing. Moreover, the application range of high strength oil porous lubricant can be broaden.

由高强多孔基体与润滑液组成的固-液仿生胞属双相复合润滑体，其结构源于生物关节软骨，现已拓宽到纤维或颗粒增强的含油孔质体领域，有效解决了极端工况下摩擦副的润滑自补偿难题；然而，这种多孔表面具有明显的局域润滑特征，其对宏观润滑膜的连续性影响及其可控性仍困扰工程界。.申请项目基于高强固-液仿生胞的双相弹性特征及表面多孔结构形态，提出局域润滑新概念，研究其本构特征、接触形变与润滑状态之间的互耦合机制，揭示其局域润滑与宏观润滑互作用机理，并探讨其润滑可控策略。研究内容涉及：(1)固-液仿生胞双相复合体多尺度结构表征及其宏观接触力学性能；(2)局域润滑效应与宏观润滑膜连续性的互作用机理；(3) 高强固-液仿生胞局域失效机理及其工况适应性；(4)局域润滑可控性及其孔胞结构重构互耦性理论。.研究可为固-液仿生胞结构设计及高强含油轴承寿命预测与可靠性分析提供理论依据；并可拓宽高强含油孔质体的工程应用范围。

高强固-液仿生胞是由有序多孔金属陶瓷基体及其润滑储液组成的固-液双相复合体，有效解决了摩擦副的耐磨性与润滑自补偿相互制约的矛盾；然而，其多孔表面明显的局域润滑特征对宏观润滑膜的连续性影响及其可控性仍困扰工程界。本项目以高强固-液仿生胞的局域润滑效应及其控制机理研究为主旨，开展了以下研究工作：.为了探讨高强固-液仿生胞的微观结构与宏观力学性能，通过微观结构测试分析其胞孔结构特征，运用多尺度均匀化理论，建立了其固-液双相复合体表征模型，利用Mori-Tanaka方法预测了该材料的复合弹性模量，并与Yaman试验数据对比验证了模型的有效性。以4129型航天润滑油为例，探讨了润滑油特性的改变对该材料复合弹性模量的影响。.以多孔金属陶瓷为基体，以Sn-Ag-Cu系低熔合金为固体润滑剂，采用真空/压力熔渗技术制备了具有高强仿生胞的Sn-Ag-Cu/金属陶瓷自润滑材料，研究了该材料与2Cr13钢盘及Al2O3陶瓷盘配副时的高温摩擦磨损性能及其润滑机理，分析了多孔表面局域润滑剂的析出与宏观润滑膜形成的关系，揭示了其局域润滑效应与宏观润滑膜连续性的互耦合机理。.为了揭示高强金属陶瓷仿生胞的工况适应性及其局域润滑失效机理，制备了Sn-Ag-Cu/金属陶瓷仿生胞自润滑滚动体，通过高温摩擦磨损试验，研究了其在不同工况条件下的摩擦学特性及自润滑机理，分析了导致润滑膜破坏的主要因素，揭示了温度、载荷、配副材料等对润滑膜的完整性和连续性的影响规律。.采用真空/压力浸渍技术将TiO2硅油纳米胶体浸渍到多孔金属陶瓷基体中，对其固-液仿生胞的结构进行重构，制备出新的TiO2硅油-金属陶瓷自润滑材料，通过高温摩擦磨损试验和SEM分析，揭示了贮存在多孔金属陶瓷中的润滑胶体参与自润滑的摩擦过程：在油膜破裂的情况下，胶体中的纳米颗粒被吸附到摩擦表面，在阻止摩擦副的直接接触的同时，产生微滚动效应，从而提高了材料的承载能力和润滑性能。.拓展研究了高强仿生胞涂层的制备装置及制备工艺，设计了新的电弧喷涂刚性送丝机，研制了高效稳定涂层预制备火焰喷涂枪，采用感应熔涂-等温淬火热处理复合新工艺，制备了具有优异涂层组织、力学性能及摩擦学性能的仿生胞涂层。.本研究为实现固-液仿生胞的润滑可控性，改善其润滑稳定性与可靠性，拓宽其工程应用范围奠定了基础，具有重要的理论意义与工程价值。