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用一种新工艺——泥浆凝胶工艺制备了石墨材料抗氧化梯度膜，通过初级泥浆涂层和合理的实验参数控制，生成了致密的ＳｉＣ涂层。通过Ｘ射线衍射对涂层进行晶相分析，用扫描电镜分析涂层的成分，证实涂层中ＳｉＣ浓度呈梯度分布，因而缓和了涂层与基体间的热应力。氧化实验表明样品在１０００℃下氧化３００ｈ、１４００℃２００ｈ以及１６００℃、２０ｈ样品质量没有任何损失。１４００℃下经２０个热循环试验后样品完好无损
An anti-oxidation gradient film of graphite material was prepared by a new process - slurry gel process. Through the primary mud coating and reasonable experimental parameters control, a dense SiC coating was formed. The coating was analyzed by X-ray diffraction (XRD). The composition of the coating was analyzed by scanning electron microscopy. The SiC concentration in the coating was confirmed to be gradient distribution, which reduced the thermal stress between the coating and the substrate. Oxidation experiments showed that the samples were oxidized at 1000 ℃ for 300h, 1400 ℃ for 200h and 1600 ℃ for 20h without any loss of sample quality. Samples were intact at 1400C for 20 thermal cycling tests