摘要
为提高石墨的耐烧蚀性能,利用压力浸渗方法将AlSi合金渗入石墨孔隙中获得石墨/AlSi耗散防热复合材料。利用小型烧蚀实验发动机开展了不同推进剂和压强工况下石墨/AlSi耗散防热复合材料喉衬和C/C喉衬的对比烧蚀试验研究,总结了推进剂铝含量、燃烧室压强对相对烧蚀性能影响,并分析石墨/AlSi耗散防热复合材料的抗烧蚀机理。结果表明,石墨/AlSi耗散防热复合材料喉衬线烧蚀率低于相同状态下C/C材料喉衬的线烧蚀率,其中在铝质量含量5%、压强12.5 MPa工况中石墨/AlSi喉衬线烧蚀率降低92%。分析认为石墨/AlSi耗散防热复合材料的抗烧蚀机理主要为:石墨孔隙内的AlSi合金通过熔化和气化相变吸收热量,降低了石墨基体的热负载;AlSi合金的熔化后在表面形成的液态膜阻碍了燃气中氧化性成分向石墨基体中的扩散;合金气化产生的Al、Si蒸气在引射作用下注入边界层,与边界层中氧化组分发生反应,降低其中的氧化组分浓度;AlSi合金氧化后形成的Al2O3 SiO2玻璃态熔融层减弱燃气对喉衬机械剥蚀作用。最终石墨/AlSi耗散防热复合材料喉衬表现出优异的抗烧蚀性能。
In order to improve the ablation resistance of graphite,AlSi alloy was infiltrated into the graphite pores by pressure infiltration method to obtain graphite/AlSi dissipative thermal protective composites.Small solid rocket motor tests have been used to compare the ablation performance of graphite/AlSi composites throat and C/C composites throat under different propellant combus tion and chamber pressure conditions.The study summarizes the effect of propellant aluminum content and combustion chamber pres sure on the relative ablation performance and the corresponding anti ablative mechanism of graphite/AlSi dissipative thermal protec tive composites.Results show that the linear ablation rate of the graphite/AlSi composites throat is lower than that of the C/C com posites throat under each attempted condition.In particular,the ablation rate of graphite/AlSi composites throat reduce by 92%com pared to C/C composites throat when the aluminum content and chamber pressure are 5%and 12.5 MPa,respectively.The AlSi alloy in the graphite pores absorbs heat through melting and vaporizing phase transitions,reducing the thermal loading of the graphite ma trix.The liquid AlSi alloy film covering on the surface prevents diffusion of oxidizing components into the graphite matrix.In addition,Al and Si vapors generated by the vaporization react with the oxidizing components in the boundary layer to reduce their concentra tions.Furthermore,the Al2O3 SiO2 glassy molten layer formed by AlSi alloy weakens the mechanical erosion of the gas flow.Thus,the graphite/AlSi dissipative heat resistant composite throat liner show excellent anti ablation performance.
作者
邓恒
刘豪
严鸥鹏
李卫鹏
康鹏超
武高辉
惠卫华
刘旸
DENG Heng;LIU Hao;YAN Oupeng;LI Weipeng;KANG Pengchao;WU Gaohui;XI Weihua;LIU Yang(Institute of Modern Control Technology,Xi'an 710065,China;School of Material Science and Engineering,Harbin Institute of Technology,Harbin 150001,China;Science and Technology on Combustion,Internal Flow and Thermo Structure Laboratory,Northwestern Polytechnical University,Xian 710072,China)
出处
《固体火箭技术》
EI
CAS
CSCD
北大核心
2020年第1期66-71,共6页
Journal of Solid Rocket Technology
基金
武器装备预研基金
关键词
固体火箭发动机
喉衬烧蚀
耗散防热材料
C/C复合材料
solid rocket motor
nozzle throat erosion
dissipative thermal protective composites
C/C composites
