Zr-Si合金熔渗改性C/C复合材料的微观结构及耐高温氧化机理研究  

Microstructure and anti-oxidation mechanism of C/C composites modified by Zr-Si alloy at high temperature

作　　者：胡鹏飞[1,2] 马村成 谢忱 宋绍雷 湛方翊[1] 甄强 Hu Peng-fei;Ma Cun-cheng;Xie Chen;Song Shao-lei;Zhan Fang-yi;Zhen Qiang(Key Laboratory for Microstructures,Shanghai University, Shanghai 200444, China;Nano Science ＆ Tech- nology Research Center, Shanghai University, Shanghai 200444, China)

机构地区：[1]上海大学微结构重点实验室,上海200444 [2]上海大学纳米科学与技术研究中心,上海200444

出　　处：《炭素技术》2018年第2期18-22,共5页Carbon Techniques

基　　金：国家自然科学基金项目(No.51472156)

摘　　要：采用Zr-Si合金在较低温度下熔渗制备了不同密度的C/C-ZrC复合材料,研究了不同密度C/C多孔体的熔渗行为以及不同密度复合材料的相组成和微观形貌,并且在1 500℃下对其静态氧化行为进行了研究。结果表明:中等密度多孔体熔渗较为理想,气孔率仅为4.78%。随着原材料密度的增加,C/C-ZrC复合材料密度增量相应下降。物相分析显示,C/C-ZrC复合材料由C,ZrC,Zr和Zr_2Si组成,未发现SiC相的存在。微观结构解析表明,反应生成的ZrC陶瓷相主要集中在网胎层,合金除与C基体反应生成ZrC层外,在熔体内部也有部分ZrC析出。论文从界面反应以及元素扩散的角度探讨了熔渗机理。C/C-ZrC复合材料在1 500℃静态氧化后的产物主要包括单斜相ZrO_2和非晶态SiO_2,未能形成致密氧化膜,改性后的样品失重率随着熔渗增重增大而减小。The C/C-ZrC composites with different densities were prepared by infiltration of Zr-Si alloy at low temperature. The in- filtration behavior of C/C porous bodies with different densities and the phase composition of different density composites were stud- ied. And the static oxidation behavior of the composites obtained was studied at 1 500 ℃. The results show that the porosity of the medium density porous body is only 4.78%. With the increase of the density of raw materials, the density increment of C/C-ZrC composites decreased correspondingly. The results show that the C/C-ZrC composites consist of C, ZrC, Zr and Zr2Si, and the SiC phase is not found. The mierostruetural analysis shows that the ZrC ceramic phase is mainly concentrated in the web layer, in addi- tion to the Zr matrix formed by the reaction with the C matrix, some ZrC precipitates in the melt. The mechanism of infiltration is discussed from the point of view of interface reaction and element diffusion. The products of C/C-ZrC composites after static oxida- tion at 1 500 ℃ mainly include monoclinic ZrO2 and amorphous SiO2, which cannot form dense oxide film. And the weight loss rate of the modified samples decreases with the increase of infiltration.

关 键 词：C/C复合材料 ZrC改性 微观结构 氧化机理 

分 类 号：TB333[一般工业技术—材料科学与工程]