化学气相沉积SiC涂层的制备及水热腐蚀行为  

Preparation and hydrothermal corrosion behavior of SiC coating by chemical vapor deposition

作　　者：毛健 陈招科[1] 徐振男 熊翔[1] MAO Jian;CHEN Zhaoke;XU Zhennan;XIONG Xiang(State Key Laboratory for Light Weight and High Strength Structural Materials,Central South University,Changsha 410083,China)

机构地区：[1]中南大学轻质高强结构材料国家级重点实验室,长沙410083

出　　处：《粉末冶金材料科学与工程》2024年第5期373-383,共11页Materials Science and Engineering of Powder Metallurgy

摘　　要：采用化学气相沉积法在高纯石墨块上制备SiC涂层,并进行水热腐蚀实验,研究化学气相沉积工艺、涂层形貌结构与涂层水热腐蚀行为的关系。结果表明:随稀释氢气流量增大,涂层平均晶粒尺寸减小,涂层出现游离Si的可能性增大,其耐水热腐蚀性能逐渐降低;随沉积温度从1 000℃升高至1 300℃,涂层结晶度和平均晶粒尺寸都先增大后减小,在沉积温度为1 200℃时获得最大值,水热腐蚀后涂层结构和晶粒形貌保持完好;随三氯甲基硅烷水浴温度升高,涂层的平均晶粒尺寸增大,50℃水浴温度下制备的涂层结晶度最差且被腐蚀得最严重。SiC coating was prepared on high-purity graphite using chemical vapor deposition method,and hydrothermal corrosion experiment was conducted to study the relationship between chemical vapor deposition process,coating morphology and structure,and coating hydrothermal corrosion behavior.The results show that with the increase of dilution hydrogen flow rate,the average grain size of the coating decreases,the possibility of free Si appearing in the coating increases,and the resistance to hydrothemal corrosion gradually decreases.As the deposition temperature increases from 1000℃to 1300℃,the crystallinity and average grain size of the coating first increases and then decreases.The maximum value is obtained at a deposition temperature of 1200℃,and the coating structure and grain morphology remain intact after hydrothermal corrosion.As the temperature of the methyltrichlorosilane water bath increases,the average grain size of the coating increases.The coating prepared at a water bath temperature of 50℃has the worst crystallinity and is the most severely corroded.

关 键 词：SIC涂层 化学气相沉积 水热腐蚀 晶粒尺寸 结晶度 

分 类 号：TB332[一般工业技术—材料科学与工程]