反应熔渗制备C/C-HfC-SiC与C/C-HfC-ZrC-SiC 复合材料对比研究-中国材料进展

文章信息/Info

Title:: Comparative Study of C/C-HfC-SiC and C/C-HfC-ZrC-SiC Composites Fabricated by Reactive Melt Infiltration

作者:: 刘芙群1; 谭杰1; 陈耘田2; 孙威2; 徐永龙2; 熊翔2; （1.中国运载火箭技术研究院, 北京 100076）（2.中南大学粉末冶金研究院, 湖南长沙 410083）

Author(s):: LIU Fuqun1; TAN Jie1; CHEN Yuntian2; SUN Wei2; XU Yonglong2; XIONG Xiang2; （1. China Academy of Launch Vehicle Technology, Beijing 100076, China） (2. Powder Metallurgy Institute, Central South University, Changsha 410083, China）

Keywords:: C/C-HfC-ZrC-SiC composites; C/C-HfC-SiC composites; ablation resistance; reactive melt infiltration

摘要:: 以C/C纤维预制体和Zr粉、Hf粉以及Si粉为原料，采用反应熔渗法制备了不同陶瓷相比例的HfC-SiC两元陶瓷与HfC-ZrC-SiC三元陶瓷改性C/C复合材料，采用扫描电镜(SEM)、能谱仪(EDS)、X 射线衍射仪（XRD)分析其形貌、成分和结构，对比了其微观结构与抗烧蚀性能，探讨了熔渗机理。结果表明，Si含量的增加有利于熔渗效果，但过量Si会降低烧蚀性能。当混合熔渗料中Si质量分数达到40%时，C/C-HfC-ZrC-SiC复合材料中细晶粒的ZrHfC固溶物分布最为均匀，有效提高了其抗烧蚀性能。烧蚀后，C/C-HfC-ZrC-SiC复合材料表面产生了一层完整致密的氧化层，而C/C-HfC-SiC复合材料表面形成了多孔的氧化层。HZS4（熔渗料中Hf,Zr和Si质量比为30∶30∶40）改性复合材料的质量烧蚀率和线烧蚀率分别为0.08 mg·cm-2·s-1和-3.30 μm·s-1，相比于HS4（熔渗料中Hf和Si质量比为60∶40）改性的复合材料，质量烧蚀率下降了46.7%。

Abstract:: Carbon/carbon composites modified by HfC-SiC and HfC-ZrC-SiC were fabricated by reactive melt infiltration. A comparative study of their microstructure, ablation behavior and infiltration mechanism was conducted by SEM, EDS and XRD. Results indicated that the increase of Si content was beneficial to the infiltration effect, but excess Si reduced composites-ablation performance. When the silicon mass fraction of infiltration mixture reached 40%, fine grains of ZrHfC solid solutions evenly distributed in the C/CHfCZrCSiC composites, which significantly improved its ablation resistance. A dense and continuous oxide layer formed on the ablated surface of C/C-HfC-ZrCSiC composites, while for the C/CHfCSiC， the oxide scales were porous. C/C-HfC-ZrC-SiC exhibited better anti-ablation resistance, and the mass ablation rate and linear ablation rate of the composite(infiltrated with the mixture in which Hf, Zr and Si mass fraction ratio is 30∶30∶40) were 0.08 mg·cm-2·s-1 and -3.30 μm·s-1, respectively. Compared with C/C-HfC-SiC(infiltrated with the mixture in which Hf and Si mass fraction ratio is 60∶40), the mass ablation rate of C/C-HfC-ZrC-SiC decreased by 46.7%.