Abstract: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.