动密封功能界面劣化机理和性能调控

Functional interface of various types of seals is studied in this project in which research on degradation mechanism and regulation of functional interface of dynamic seals is going to be carried out. The research includes following contents: 1. Through research on the mechanism of interface instability between working medium and sealed medium, the interaction between evolution of polymer material properties and the Interface function and the wear mechanism and evolution law of mixed lubrication, damage accumulation effect in the rub-impact interface, degradation law of functional interface can be revealed. 2. Establish mathematical model to discuss the evolution of interface performance over time. 3. Predict the changes of sealing performances in actual condition. 4. By changing properties of the working medium composition, controlling external conditions, optimizing material matching pairs and manufacturing process and so on, regulation of functional interface of dynamic seals could be achieved. Taken together, a sealing design method considering influence of degradation of functional interface is proposed to improve the reliability of sealing and prolong the service life. Furthermore, this project can provide theoretical basis to solve critical sealing problems in nuclear power, space aviation, aerospace, marine, petrochemical and other fields.

本课题以各种类型动密封中具有共性的主要元素——功能界面为研究对象，对其性能的劣化机理和调控方法开展研究。通过研究工作介质/密封介质界面失稳机理、聚合物材料特性演化与界面功能之间的相互影响规律、界面混合润滑磨损机理与演化规律、碰摩界面损伤累积效应等揭示密封功能界面性能劣化规律；建立功能界面性能随时间演变的数学模型；预测密封性能使役工况下的性能演变规律；通过工作介质成分改性、外部条件控制、材料配副优化、表面设计及工艺过程优化等手段实现功能界面的性能调控, 最终提出考虑动密封功能界面劣化影响的密封设计方法，提高密封工作可靠性、提升寿命质量、延长使用寿命，为解决核电、航空、航天、航海、石化等领域的关键性密封问题提供理论基础。

密封是防止介质泄漏的技术手段，对重大装备和主机的性能、质量、可靠性具有重要影响。对于高可靠性要求的国防、能源等领域，密封往往直接决定了整套装备的寿命与运行安全。动密封服役过程中，密封材料和介质性能随服役时间逐渐劣化，影响密封性能。掌握动密封劣化机理和规律，是密封领域亟待解决的难题。本项目围绕以磁性液体密封为主要代表的多种典型动密封开展研究，以动密封功能界面为研究对象，从工作机理与载荷特性、劣化机理与规律、设计与调控等方面开展综合性研究，提出了多种密封功能界面多场耦合模型，从多个角度研究了密封功能界面的劣化机理，发展了一系列密封功能界面的调控手段。项目提出了提出了磁性液体密封功能界面多场耦合模型，成功制备耐酸碱、低挥发的高性能磁性液体，提出了多元磁性液体密封功能界面调控与优化设计方法，提出了磁性液体掺杂碳纳米管、二氧化硅等材料的改性方法，在真空、化工等多个领域获得成功应用。