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卫星和航天器的推进系统装上了使用高性能四氧化二氮和一甲基肼双元推进剂的火箭发动机已取得成功,其原因之一是其燃烧室和出口喷管使用了高熔点的材料体系。阿波罗服务舱和登月舱上使用的推力为445N的姿态控制火箭发动机就是以钼用作燃烧室材料。不久这一材料体系又被铌合金材料体系所取代,后者目前主要用在小型液体火箭发动机上。带R-512氧化涂层的材料约1600℃的工作极限,足以满足近乎2900NSec/kg的试验性能水平,但涂层与基体金属之间在结构和力学性能上的差异,限制了燃烧室在该温度下经受热循环时的工作时间。已经对象碳化硅基体系统、氧化铼和氧化锆等新材料系统作了评定,并通过实验说明其承受温度能力逐步增加,而对保持在空间站和在轨道期间姿态控制火箭发动机工作的热循环特性并不敏感。欧洲推进协会(Societe Europeenne de Propulsion)用碳化硅材料系统进行了试验,玛夸特(Marguardt)公司用层压的铼和锆的氧化物基体材料系统进行了试验,这些试验都证明了在较高的发动机性能水平条件下增加了使用寿命,燃烧室温度为2100℃时所提供的比冲性能水平为3000NSec/kg。
One of the reasons that satellites and spacecraft propulsion systems have been equipped with rocket motors using high-performance dinitrogen monosulfide and monomethylhydrazine binary propellants is that their combustion chambers and outlet nozzles use high-melting Material system. The 445N thrust control rocket engine used on the Apollo service and lunar module uses molybdenum as the combustion chamber material. Soon after, the material system was replaced by a system of niobium alloys, which are currently used mainly on small liquid rocket engines. The working limit of the material with the R-512 oxide coating is about 1600 ° C, which is sufficient to meet the experimental performance level of almost 2900 NSec / kg but the difference in structure and mechanical properties between the coating and the base metal limits the combustion chamber Operating temperature when subjected to thermal cycling. New material systems such as silicon carbide substrate systems, rhenium oxide and zirconium oxide have been evaluated and experimentally demonstrated that their ability to withstand temperature increases progressively while thermal cycling characteristics of attitude-controlled rocket motors remain in space station and during orbit Not sensitive. The European Association for Propulsion (EPE) conducted a test with a silicon carbide material system, and Marguardt conducted tests with laminated rhenium and zirconium oxide matrix systems, all of which demonstrated that at higher Of the engine performance level increased life expectancy, the combustion chamber temperature of 2100 ℃ provided when the specific performance level of 3000NSec / kg.