镍对C/SiC化学气相渗透碳的催化研究

Study of Catalysis Effect of Ni on CVI PyC Process

用液相浸渗还原法将Ni渗入C/SiC复合材料,研究复合材料中Ni对化学气相渗透PyC过程的影响。用重量分析法研究Ni的催化作用,用扫描电子显微镜(SEM)、X射线衍射(XRD)技术分析材料的微观结构及组成。结果表明,Ni对化学气相渗透PyC具有催化作用,它加速了PyC的沉积,Ni含量为4.4%时增重率达最大值9.98%。沉积的PyC为细小颗粒聚集体。CVI过程中Ni与基体SiC反应生成Ni2Si,Ni3Si。

Nickel was infiltrated into the carbon/silicon carbide （C/SiC） composite by liquid impregnation and reduction method. The influence of nickel on the process of chemical vapor infiltration of carbon has been investigated. The catalysis of nickel was studied by weight analysis, the microstructure of the material was observed by SEM and the composition was analyzed by XRD. The results shows that nickel infiltrated into C/SiC composites accelerates the deposition of carbon in the material. The mass gain rate of carbon reached the maximum （9.98%） when nickel content was 4.4%. The carbon deposited is aggregative state consisting of fine particles. During CVI process, nickel reacts with silicon carbide to form Ni2Si and Ni3Si.