C/C-SiC-HfB2多元陶瓷基复合材料烧蚀机理分析  

Oxidation ablation resistance mechanism of C/C-SiC-HfB2 composite

作　　者：田蔚[1] 白侠[1] 郭春园[1] TIAN Wei;BAI Xia;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

出　　处：《固体火箭技术》2019年第6期724-729,共6页Journal of Solid Rocket Technology

基　　金：国家自然科学基金(21676163)

摘　　要：针对C/C复合材料抗氧化性能差的问题,采用化学气相沉积和先驱体浸渍裂解炭化复合致密方法制备出密度为1.85 g/cm^3的C/C-SiC-HfB2复合材料,通过氧乙炔火焰烧蚀测试了材料的质量烧蚀率和线烧蚀率,借助SEM、XRD和能谱等观察分析了微观结构及物相变化,详细研究并阐述了C/C-SiC-HfB2复合材料的高温抗氧化烧蚀机理。结果表明,制备的C/C-SiC-HfB2复合材料烧蚀率低,质量烧蚀率为0.001 g/s,线烧蚀率为0.003 mm/s;良好的烧蚀结果是因为在烧蚀过程中,在材料表面形成HfO2热障材料层、致密的SiO2玻璃层和SiO2/HfO2氧化复合层,阻碍了氧气和热量从表面向材料内部的传递,使氧化烧蚀行为只限于表面,保护了材料内部不受破坏,提高了材料的高温抗氧化、抗烧蚀性能。In order to improve the oxidation resistance of C/C composite,the C/C-SiC-HfB2 composite,whose density was about 1.85 g/cm^3,was deposited by a combination densification process of chemical vapor infiltration and resin liquid impregnation/carbonization in this paper.The ablation of C/C-SiC-HfB2 composite was tested by oxyacetylene torch equipment.The microstructure and phase transformation of C/C-SiC-HfB2 composite were observed by using SEM,XRD and energy spectrum.The results show that the average mass loss and the liner ablation of C/C-SiC-HfB2 composite after oxyacetylene torch test are 0.001 g/s and 0.003 mm/s,respectively.This excellent oxidation ablation resistance is possibly due to the generated thermal barrier material covering on sample surface during the test.The generated thermal barrier material prevented O 2 and heat from surface to inner part of the composite.Microstructure and XRD analysis on the cross-section of composite reveal that the thermal barrier material covering mainly consists of HfO2,SiO2 and SiO2/HfO2,which could improve the thermal oxidation resistance of composite.

关 键 词：C/C-SiC-HfB2复合材料 微观结构 烧蚀性能 烧蚀机理 

分 类 号：V250.3[一般工业技术—材料科学与工程]