RMI法制备穿刺C/C-SiC复合材料的微结构及烧蚀性能  

Microstructure and Ablation Properties of the Pierced C/C-SiC Composites Prepared by Reactive Melt Infiltration

作　　者：吴小军[1] 刘明强[1] 张兆甫 谢栋[1] 郭春园[1] Wu Xiaojun;Liu Mingqing;Zhang Zhaofu;Xie Dong;Guo Chunyuan(Xi’an Aerospace Composites Research Institute,Xi’an 710025,China)

机构地区：[1]西安航天复合材料研究所,陕西西安710025

出　　处：《稀有金属材料与工程》2021年第11期4023-4030,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(21676163);中国航天青年拔尖人才项目(2019.1-2021.12)。

摘　　要：以无纬布/网胎0°/90°叠层穿刺三维四向预制体为增强体,采用化学气相渗透(chemical vapor infiltration,CVI)、树脂浸渍碳化(polymer infiltration carbonization,PIC)与反应熔渗(reactive melt infiltration,RMI)复合工艺制备穿刺C/C-SiC复合材料,研究其微观组织及在C_(2)H_(2)-O_(2)焰中的烧蚀行为。结果表明:无纬布、穿刺纤维束由CVI+PIC制备的碳基体填充而形成致密C/C区域,RMI生成的SiC主要位于网胎层中,其含量为37.3%(质量分数)。复合材料表面因过量硅化而形成了SiC富集层。当烧蚀距离为20 mm、O_(2):C_(2)H_(2)=2:1时,烧蚀600 s后材料X-Y、Z向线烧蚀率分别为0.8×10^(-4)、3.6×10^(-4) mm/s,比先驱体浸渍裂解(polymer infiltration pyrolysis,PIP)工艺制备C/C-SiC材料烧蚀率小1个数量级。烧蚀面SiC富集层保护及被动氧化作用是材料具有优异抗氧化烧蚀性能的主要原因。随烧蚀距离由20 mm向10 mm减小,复合材料烧蚀率先缓慢变化后快速增大,烧蚀率快速增长阶段复合材料发生主动氧化烧蚀。The C/C-SiC composites were prepared by chemical vapor infiltration(CVI)combined with polymer infiltration carbonization(PIC)and reactive melt infiltration(RMI)using pierced non-woven carbon fiber felt preform.The microstructure and ablation properties were investigated.The results show that non-woven carbon fiber cloth and pierced carbon fiber bundle are filled with carbon matrix prepared by CVI and PIC to form dense C/C microstructure.SiC matrix is mainly located in the felt after RMI process and the content is 37.3wt%.SiC-rich layer is formed on the surface of the composites.When the ablation distance is 20 mm and the flow ratio of oxygen and acetylene is 1:2,the ablation rates on X-Y and Z directions of the composites are 0.8×10^(-4) and 3.6×10^(-4) mm/s,respectively.The excellent ablation performance could be owing to the passive oxidation of SiC-rich layer on the surface.With the ablation distance decreasing from 20 mm to 10 mm,the ablation rate of the composites changes slowly and then increases rapidly,because of the active oxidation ablation of the composites.

关 键 词：反应熔渗 C/C-SIC复合材料 氧乙炔烧蚀 微结构 

分 类 号：TB332[一般工业技术—材料科学与工程]