面向航天煤油及气体环境应用的密封件磨损失效机制及表面薄膜改性技术研究

The wear failure of nitrile rubber seal is the most important factor leading to the oil leakage of the aerospace servo tank, which directly affects the service life and safety of the spacecraft. Therefore, this project is mainly aimed at the wear failure of the aerospace servo tank accumulator seal (nitrile rubber) in aerospace kerosene and N2 working medium, Combining with the existing problems of the current studies on nitrile rubber wear mechanism, surface chemical modification, surface DLC film and other methods, the proposed superlubracation superelastical fullerene-like carbon film is design ideas to improve the surface wear resistance of nitrile rubber. In this project, the target is to study the wear failure mechanism and influencing factors of nitrile rubber under the aerospace kerosene and N2 environment, based on this wear mechanism, the magnetron sputtering combined with plasma enhanced chemical vapor deposition technique was used to fabricate superlubracation superelastical fullerene-like carbon film on its surface, to investigate the tribological characteristics and mechanism of fullerene-like carbon films under the aerospace kerosene and N2 environment, to fully understand two scientific problems including to the correlation between the debris morphology and the tribological mechanism of nitrile rubber and the tribological mechanism of soft surface bearing self-segmented fullerene-like carbon film, to break two key technology including to the high adhesion of the soft / hard matrix interface and continuous stabilitable ultra-low friction coefficient of the fullerene-like carbon film under the aerospace kerosene and N2 environment, to solve the wear failure problem of the servo seal in the high-pressure aerospace kerosene and N2 medium, to meet the long-life and reliability service requirements of aerospace seals.

丁腈橡胶密封件磨损失效是导致航天伺服机构油箱蓄压器渗漏油的最主要因素，直接影响航天飞行器的安全性及服役寿命。本项目主要围绕丁腈橡胶密封件的磨损失效问题，针对目前其表面耐磨损改性处理技术中的缺陷和不足，拟开展丁腈橡胶表面高结合、超弹、超滑类富勒烯结构碳薄膜改性研究。项目首先考察丁腈橡胶在航天煤油和N2工作介质中的磨损失效机制，探讨丁腈橡胶磨屑形态与其磨损失效机制的相关性规律，然后基于该机制，通过等离子体活化和薄膜结构性能优化调控在其表面设计制备高结合、超弹、超滑类富勒烯结构碳薄膜，阐明该薄膜在上述工作介质中的摩擦磨损机制，突破丁腈橡胶表面高结合、超弹类富勒烯碳薄膜在航天煤油和N2工作介质中连续稳定超滑可控制备技术，建立类富勒烯碳薄膜改性丁腈橡胶服役寿命评价方法体系，最终解决伺服机构密封件的磨损失效问题，满足航天密封件的长寿命可靠服役要求。

丁腈橡胶密封件磨损失效是导致航天伺服机构油箱蓄压器渗漏油的最主要因素，直接影响航天飞行器的安全性及服役寿命。本项目主要围绕丁腈橡胶密封件的磨损失效问题，考察了丁腈橡胶大气、氮气和航天煤油环境中，不同摩擦时间、载荷、摩擦频率等条件下的摩擦磨损行为，揭示了丁腈橡胶在氮气和航天煤油介质中的磨损失效机制；分析了不同等离子体、预处理时间和偏压对丁腈橡胶表面碳薄膜结合强度的影响规律，阐明了等离子体预活化对橡胶表面碳薄膜结合强度的作用机理；探究了丁腈橡胶表面碳薄膜在大气、氮气和航天煤油环境中的摩擦磨损行为与机制，实现了橡胶表面碳薄膜跨环境连续稳定的低摩擦特性；碳薄膜改性橡胶密封实件经4000次磨合和50小时整机寿命试验以及可靠性验证，油端和气端X型密封圈磨损情况良好，伺服机构油气一致性较好，未发生渗漏现象，破解了航天飞行器关键密封件因磨损失效导致的泄压难题。本成果可应用于所有涉及橡胶密封系统的军民用设备及装备。