(中南大學 粉末冶金國家重點實驗室, 長沙 410083)
摘 要: 以炭纖維針刺氈為預(yù)制體， 采用化學氣相沉積法(CVI)和結(jié)合液相浸漬樹脂或瀝青法制備了熱解炭為粗糙層與光滑層結(jié)構(gòu)的準三維C/C復(fù)合材料, 并研究了這些材料在0.6 MPa的模擬剎車壓力下的摩擦磨損性能與磨損機理。 研究表明： 基體炭為粗糙層熱解炭與樹脂炭的C/C復(fù)合材料摩擦表面能形成較厚且連續(xù)的自潤滑摩擦膜， 摩擦穩(wěn)定性最好， 摩擦因數(shù)適中， 氧化磨損小， 磨損機理主要為膜的部分脫落、 氧化磨損與相對較小的磨粒磨損； 基體炭為光滑層熱解炭與樹脂炭或瀝青炭的C/C復(fù)合材料摩擦表面形成的摩擦膜較薄且不連續(xù)， 摩擦穩(wěn)定性差， 摩擦磨損較大， 磨損機制主要為膜的部分脫落、 磨粒磨損與更嚴重的氧化磨損； 隨著密度的升高， C/C復(fù)合材料摩擦穩(wěn)定性增加， 摩擦因數(shù)增加， 磨損降低； 基體炭為單一瀝青炭的C/C復(fù)合材料， 由于沒有熱解炭對纖維的保護， 纖維斷裂多， 線性磨損尤其大， 磨損機理主要為大量的磨粒磨損與氧化磨損。
關(guān)鍵字: C/C復(fù)合材料； 基體炭； 摩擦磨損性能； 磨損機制
（ State Key Laboratory for Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract: The quasi-3D C/C composites with rough laminar (RL) and smooth laminar(SL) pytolytic carbon were fabricated by needled felt through CVI and impregnation with liquid pitch and resin, and their friction and wear properties under braking pressure of 0.6 MPa and worn mechanism were studied. The results show that C/C composites by resin impregnation after CVD with RL have the most stable friction properties and appropriate friction coefficient and low oxidation loss, because the friction surfaces have relatively thick and uniform lubricant friction film and the wear mechanisms are the falling off of part friction film and oxidation wear loss and relatively slight abrasion wear; C/C composites by resin or pitch impregnation after CVD with SL have unstable friction and wear properties and higher wear loss owing to the thin and discontinuous friction film, and the wear mechanisms are also the falling off of part friction film and abrasion wear and larger oxidation wear loss. The higher the density, the more stable the braking curve, and the higher the friction coefficient and the lower the wear rates. Without the protection of pyrolytic carbon, C/C composites by pitch impregnation only have the highest dimension wear rates due to the largely fracture of fibers and the wear mechanism are mainly abrasion wear and oxidation wear.
Key words: C/C composites; matrix carbon; friction and wear properties; worn mechanism
