丁腈橡胶磨损失效机制及其表面碳薄膜改性技术

针对航天伺服机构密封件因磨损失效导致的泄漏难题，分析了大气及氮气环境下丁腈橡胶磨损失效机制。在此基础上，提出了其表面硬质类金刚石碳薄膜（DLC）改性技术，分析了改性后丁腈橡胶密封实件综合性能。结果表明：大气环境、恒定载荷（小载低速）条件下，丁腈橡胶主要以分层剥落方式磨损（疲劳磨损）。随着摩擦速度（或载荷）增大，其磨损失效主要表现为粘着磨损。对于氮气环境，氮气能够有效避免摩擦界面氧化作用，即降低了粘着磨损效应；此外，改性后橡胶密封实件在机械性能、质密性和密封性等方面较原始密封件未发生明显变化。经过4000次台架磨合试验后，油端密封圈表面光洁，无异常磨损；气端密封圈表面存在轻微磨损，能够满足使用要求。

Wear Failure Mechanism and Carbon Film Modification of Nitrile Butadiene Rubber

Aiming at the leakage problem caused by wear failure of aerospace servo seals, the wear failure mechanism of nitrile butadiene rubber (NBR) in the atmosphere and nitrogen environment were analyzed. On this basis, the modification technology of hard diamond-like carbon (DLC) film on NBR was proposed, and the comprehensive properties of the modified NBR seal were analyzed. The results show that: NBR is mainly worn by delamination (fatigue wear) under atmospheric environment and constant load (low load and low speed). With the increase of friction speed (or load), the wear failure is mainly adhesive wear. For nitrogen environment, nitrogen can effectively avoid the oxidation of friction interface, namely, reduce the adhesive wear effect; And compared with the original seal, the modified rubber seal has no obvious changes in mechanical properties, quality tightness and sealing. After 4000 times bench running, the seal ring is smooth without abnormal wear at the oil end, while the slight wear can be observed on the surface of the sealing ring at the gas end, which can meet the service requirements.