SiC_F的热解碳涂层的制备  

Preparation of Pyrocarbon Coatings on SiC_F

作　　者：赵锴[1] 于新民[1] 罗发[1] 朱冬梅[1] 周万城[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2007年第A02期690-692,共3页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助(90305016)

摘　　要：以C_3H_6为源气体,N_2为稀释气,在800℃～1200℃温度范围内,SiC纤维上进行了热解碳的沉积。研究了沉积温度、系统压力和P_(N_2)/P_(C_3H_6)对热解碳沉积速率和沉积层形貌的影响。结果表明:在沉积温度低于900℃,系统总压小于1 KPa条件下,沉积速率低,难以进行热解碳的沉积。随着沉积温度、系统压力升高,沉积速率升高,沉积层形貌发生改变。过低的P_(N_2)/P_(C_3H_6)导致不均匀的热解碳沉积形貌,局部有碳颗粒的生成。沉积温度为1000℃、系统总压10KPa左右、P_(N_2)/P_(C_3H_6)为2:1的条件下可获得均匀致密的热解碳沉积层。反应热力学和动力学条件随工艺参数的改变而改变,这是热解碳沉积层形貌改变的主要原因。Pyrocarbons were deposited on SiC fibers from the gaseous mixture of C3H6 and N2 at temperatures range from 800 ℃ to 1200 ℃, The variations of deposition rate and surface morphology along with the changes of temperature, total pressure and PN2/PC3H4 have been studied, The results show that pyrocarbons could hardly be obtained under the condition where the temperature and total pressure were below 800 ℃ and 1 kPa, respectively. Deposition rate increases and the morphology ofpyrocarbons alters from uniform depositions to uneven ones with the increasing of the temperature and total pressure. Low ratio of PN2 /PC3H4 leads to pyrocarbon granulation products, Compact as well as even pyrocarbons were obtained when depositon temperature was 1000 ℃, total pressure 10kPa and PN2 /PC3H4 H, 2：1 approximately, The changes of processing parameters could result in the changes of reaction thermodynamics and kinetics, which in turn is the main reason for the changes of the surface morphology.

关 键 词：热解碳 沉积速率 形貌 丙烯 

分 类 号：TB304[一般工业技术—材料科学与工程]