(中南大學(xué) 粉末冶金國家重點實驗室，長沙 410083)
摘 要: 以碳/碳復(fù)合材料為基體，MTS為先驅(qū)體原料，采用化學(xué)氣相沉積法在復(fù)合材料表面制備CNT-SiC/SiC復(fù)合涂層；研究原位生長的碳納米管(CNTs)對SiC沉積速度和微觀形貌的影響。結(jié)果表明：CNTs加快SiC的沉積，涂層的平均質(zhì)量增加速率提高5%，提高沉積的均勻性，且晶粒更細(xì)小；經(jīng)1 100 ℃恒溫氧化10 h后，單一SiC涂層、CNT-SiC/SiC涂層的質(zhì)量損失率分別為41.11%和34.32%；經(jīng)(1 100 ℃，3 min)↔(室溫，3 min)熱循環(huán)15次后，單一SiC涂層和CNT-SiC/SiC涂層的質(zhì)量損失率分別為33.17%和30.25%，部分區(qū)域涂層脫落及涂層表面形成的氣孔是涂層試樣質(zhì)量損失的主要原因。
關(guān)鍵字: 碳/碳復(fù)合材料；CNT-SiC/SiC復(fù)合涂層；碳納米管；化學(xué)氣相沉積；氧化
deposition SiC coatings
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The CNT-SiC/SiC composite coating was deposited on carbon/carbon composites by chemical vapor deposition (CVD) with methyltrichlorosilane (MTS) as the precursor. The SiC deposition rate and surface micro- morphology of the in-situ growth CNTs sample were investigated. The results show that CNTs accelerates the SiC deposition rate and improves the deposition uniformity, the average mass gain rate is improved by 5% and finer grain SiC is obtained. After oxidation at 1 100 ℃ for 10 h, the mass losses of the single SiC and CNT-SiC/SiC coated samples are 41.11% and 34.32%, respectively. After thermal cycling between (1 100 ℃, 3 min) and (room temperature, 3 min) for 15 times, the mass losses of the single SiC and CNT-SiC/SiC coated samples are 33.17% and 30.25%, respectively. The mass loss of the coated samples is mainly resulted from the debonding of some coating and the formation of holes on the coating surface.
Key words: carbon/carbon composites; CNT-SiC/SiC composite coating; CNTs; chemical vapor deposition; oxidation
