低密度烧蚀材料研究进展

An overview on low-density ablators

随着深空探测任务发展,飞船返回舱和星际探测器的大底和侧壁等部位的高热流密度、高焓值和长气动加热时间的热环境对热防护系统及材料的气动外形保持能力、轻量化、防热效率、隔热性能和长时间服役能力提出了更高的要求,使得具有烧蚀、隔热性能优异和结构重量轻等特点的低密度烧蚀材料备受关注.文章系统总结了低密度烧蚀材料的特点和发展历程,介绍了国内外蜂窝增强和纤维化多孔基体增强两类低密度烧蚀材料的研究进展及实际应用现状,重点介绍了蜂窝增强硅橡胶、蜂窝增强酚醛树脂和蜂窝增强有机硅树脂低密度烧蚀材料,以及硅树脂浸渍可重复使用陶瓷基体烧蚀材料和酚醛浸渍碳烧蚀材料为代表的轻质陶瓷烧蚀材料.针对我国发展新一代载人飞船的近地轨道、载人登月、载人登小行星、载人登火星等任务模式热防护系统的特殊需求,介绍了国内为新一代多用途载人飞船轻量化热防护系统研制所做的基础研究和应用研究.最后,分析了低密度烧蚀材料的国内外的技术差距并探讨了我国低密度烧蚀材料发展展望.

With the development of deep-space exploration, due to their distinguished features such as good ablation low-density ablators have received increased attention performance and low structure weight to fulfill the requirement of lightweight, low ablation rate, low thermal conductivity and long re-entry time of thermal protection for heatshield and backshell of planetary entry probes and re-entry capsules. The historical prospects on development of low-density ablative thermal protection systems and materials were introduced with emphasis on low- density honeycomb reinforced silicon rubber, phenolic and organic silicone resin ablators, as well as the typical representative of light weight ceramic ablators （LCAs） such as silicone impregnated reusable ceramic ablator （SIRCA） and phenolic impregnated carbon ablator （PICA）. According to the task requirements of China＇ s new- generation manned spacecraft, including low earth orbit flight mission, as well as manned flights to the Moon, the asteroid and the Mars, the progress of basic and applied research on lightweight thermal protection system for the spacecraft was presented. And then, it analyzes the technology gap between domestic and foreign, and provides several suggestions concerning the prospects of China＇ s low-density ablators.