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以国内某发动机在飞行过载下绝热层的异常烧蚀为研究背景,基于地面过载模拟装置,模拟了飞行过载条件下的颗粒冲刷状态参数,针对不同配方体系的绝热材料开展了筛选试验以及烧蚀特性研究,实验获得了三种材料的最大炭化烧蚀率和质量烧蚀率,筛选出了实验条件下抗颗粒冲刷能力较强的绝热材料,并针对实验后绝热材料的炭化层进行了电镜扫描分析,结合绝热材料配方开展了抗烧蚀特性分析。研究结果表明:(1)在实验条件下,材料B的炭化烧蚀率和质量烧蚀率均最大,材料A的居中,材料A1的最小,材料A1的抗颗粒冲刷性能最佳;(2)由于芳纶纤维的原位成炭特性,决定了三元乙丙/芳纶纤维体系绝热材料的炭化层具有一定结构强度,而恰当的纤维和SiO2含量将会增强绝热材料的抗烧蚀性能;(3)根据研究结果,建议在工艺允许的情况下,可以考虑研制同时采用芳纶纤维和石棉纤维的绝热材料体系,在针对颗粒冲刷条件时,炭化层内即有可以形成骨架结构的芳纶纤维,又可以利用石棉纤维在受热分解时SiO2和MgO熔融后和纤维以及基体之间的粘结交联效应。
Based on the ablation abnormity of an engine over flight overburden in China, based on the ground overloading simulator, the parameters of particle scouring under flight overloading conditions were simulated. The screening tests and ablation of heat insulating materials with different formulation systems were carried out. Characteristics of the experiment, the maximum carbonization ablation rate and mass ablation rate of the three materials were obtained experimentally, screened the insulation material with strong anti-particle scouring ability under the experimental conditions, and the carbonized layer of the thermal insulation material was examined by the electron microscope Analysis, combined with insulation formula developed anti-ablation characteristics. The results show that: (1) Under the experimental conditions, the carbonization ablation rate and mass ablation rate of material B are the highest, material A is the center, material A1 is the smallest and material A1 is the best. (2) Due to the in situ carbonization of aramid fiber, the carbonized layer of the EPDM / aramid fiber system has certain structural strength, and the proper fiber and SiO2 content will enhance the ablation resistance of the insulation. (3) According to the results of the study, it is suggested that when the process allows, we can consider the development of the insulation material system which uses both aramid fiber and asbestos fiber. When aiming at the particle scouring condition, the aramid Fiber, but also can take advantage of the asbestos fibers in the decomposition of SiO2 and MgO melt and fiber and matrix bonding between the crosslinking effect.