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烧蚀材料是再入航天器最常用的防热材料。本文采用EMPA、XRF和DTA -TG等现代分析测试手段研究了玻璃纤维增强酚醛型烧蚀材料的显微结构及其烧蚀过程。研究表明 :烧蚀材料在烧蚀后断面形成三个区域 :炭化区、有机树脂热解区和原始材料区。玻璃纤维在高温下熔融而在炭化区表面形成一层玻璃相。玻璃纤维的直径为 8～ 9μm ,是一种硅酸盐玻璃纤维 ,属于Na2 O -CaO -SiO2 三元系统。热分析结果显示烧蚀材料存在二个明显的失重区 ,一个放热峰和 5个吸热峰。这些热效应是和一系列的烧蚀反应密切相关的
Ablative materials are the most commonly used heat-resistant materials for reentry spacecraft. In this paper, the modern analytical methods such as EMPA, XRF and DTA-TG are used to study the microstructure and ablation process of glass fiber reinforced phenolic ablative materials. The results show that the ablated material has three sections after ablation: carbonization zone, organic resin pyrolysis zone and raw material zone. The glass fiber melts at a high temperature to form a glassy phase on the surface of the carbonization zone. Glass fiber diameter of 8 ~ 9μm, is a silicate glass fiber, belonging to Na2 O -CaO -SiO2 ternary system. The thermal analysis results show that there are two distinct regions of ablation weight loss, one exothermic peak and five endothermic peaks. These thermal effects are closely related to a series of ablation reactions