摘要: |
石英纤维增强石英陶瓷基(SiO2f/SiO2)复合材料因其固有特性易发生吸潮,严重影响其透波性能,通过对SiO2f/SiO2复合材料进行疏水改性、封孔层及面漆层处理得到高性能防潮涂层。涂层具有优异的疏水性,封孔层有效填充孔隙,同时面漆层形成致密薄膜,进一步提高整体防潮性能。涂层附着力、介电性能皆满足使用要求,涂敷防潮涂层后,样品24h泡水增重率从10%降至0.4%,交变湿热吸湿率从8%降至0.6%。涂层将SiO2f/SiO2复合材料的弯曲强度提高了33.9%。经过石英灯烧蚀,涂层碳化极少,表明其高温透波性能优异。此外,涂层通过组合级环境试验,该防潮涂层可有效解决航天透波结构件的吸潮难题。 |
关键词: SiO2f/SiO2复合材料;防潮涂层;疏水性;吸湿率;介电性能 |
基金项目: |
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Properties of Moisture-proof Coating of SiO2f/SiO2 Wave-transparent Composites |
Mao Bangxiao Xia Xisheng Li Chunhui Zhang Xiaofei Liu Wei Yang Guangren Fu Huibin Lv Haihua Xu Donghong
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Beijing Xinfeng Aerospace Equipment Co., Ltd., Beijing 100854
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Abstract: |
Quartz fiber reinforced quartz ceramic matrix SiO2f/SiO2 composites is prone to moisture absorption due to the inherent characteristics, which seriously affects the wave-transparent property. The SiO2f/SiO2 composites is subjected to hydrophobic modification, hole sealing layer and topcoat layer to obtain a high-performance composite moisture-proof coating. The coating has excellent hydrophobicity. The hole sealing layer effectively fills the pores, and at the same time the topcoat layer forms a dense film to further improve the moisture resistance. The coating adhesion and dielectric properties meet the requirements. After the moisture-proof coating is applied, the weight gain rate of the sample decreases from 10% to 0.4% after soaking in water for 24h, and the moisture absorption rate decreases from 8% to 0.6% after the alternating humidity and temperature test. The coating increases the bending strength of the SiO2f/SiO2 composites by 33.9%. After the ablation of the quartz lamp, the coating carbonization is very little, indicating that the wave-transparent property of high-temperature is excellent. In addition, the coating passes the combinatorial environmental test. The moisture-proof coating can effectively solve the moisture absorption problem of aerospace wave-transparent structural parts. |
Key words: SiO2f /SiO2 composites;moisture-proof coating;hydrophobicity;moisture absorption rate;dielectric properties |