共查询到18条相似文献,搜索用时 140 毫秒
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聚甲基丙烯酰亚胺(PMI)泡沫夹层复合材料具有优异的宽频透波性能,被广泛用于制备透波雷达天线罩。为了设计满足宽频透波要求的某型天线罩,从复合材料结构原理出发,选择石英纤维增强环氧树脂复合材料为蒙皮,PMI泡沫为芯材的A夹层结构方案,采用三维全波电磁场仿真软件(CST软件)计算比较了不同蒙皮厚度和芯材厚度对A夹层结构透波性能的影响,得到了理论最优结构。进一步的平板试验结果表明,透波率的实际测试值与理论计算结果基本吻合,可见设计的A夹层复合材料结构可满足某型天线罩的宽频透波要求。 相似文献
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高频透波玻璃钢天线罩性能的研究 总被引:2,自引:0,他引:2
通过对玻璃钢天线罩增强材料基体材料性能的引述,实验分析了不同成型工艺对高频玻璃钢天线罩透波性能的影响,同时对玻璃钢天线罩单板壁厚进行研究,通过试验论证产品中采用不同高度的蜂窝对高频天线罩的影响。 相似文献
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石英/氮化物复合材料防潮涂层的制备及性能研究 总被引:1,自引:0,他引:1
石英/氮化物复合材料具有优异的综合性能,可用作高马赫数导弹天线罩材料.采用先驱体浸渍裂解法制备的该复合材料存在易吸潮的缺点,吸潮后会影响其透波性能.研究制备了复合材料的聚偏氟乙烯(PVDF)涂层.测试发现,聚偏氟乙烯(PVDF)涂层具有优良的防潮性能,在40℃、90%高温高湿条件下放置70d的增重率为0.934%.PVDF涂层对复合材料的透波性能影响较小,涂覆厚度约300μm的涂层前后介电常数及介电损耗分别为3.48、0.0051和3.62、0.0053. 相似文献
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《玻璃钢/复合材料》2020,(6)
提出一种复合材料机载天线罩多学科优化策略。以满足天线罩透波率为要求,基于等效传输线理论,对天线罩电性能进行分析,找出符合电性能指标的铺层厚度区间,将对透波率的约束转换到设计变量铺层厚度中。在满足透波率要求的前提下,建立了以质量最小为目标,结构刚度强度为约束,罩壁不同方向铺层厚度为设计变量的优化数学模型,以实现天线罩的轻量化设计。以某A-夹层机载天线罩为例进行了优化分析,研究结果表明,优化后的天线罩有显著的轻量化效果和较高的透波率表现,验证了优化方法的可行性。 相似文献
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An electromagnetically transparent, structurally robust and environmentally resistant enclosure of radar antenna for ground based systems to modern avionics in military aircraft and missiles is called as radome. Radome materials are classified based on: (i) type of function - surface-based or flight-mode and (ii) speed of operation - subsonic, supersonic to hypersonic. The desired properties of these materials are low dielectric constant and low loss factor in addition to its capacity to withstand the high temperature of operation. Composite laminates of glass or aramid fibre reinforced polymeric resins are radome material candidates for applications in subsonic range. However, ceramics are the only viable option for military aerospace applications such as a fighter jet travelling at Mach 3 or an advanced hypersonic missile speeding up to Mach 5. This review outlines the hand-full of ceramic materials already in application as radome materials like high-purity-alumina, pyroceram, slip-cast-fused-silica, their processing technology, electromagnetic and mechanical properties, advantages and disadvantages with respect to advanced military vehicles. Use of silicon nitride based radome materials, that has exceptional mechanical strength and thermal stability up to 1400 °C is illustrated with respect to reaction bonded silicon nitride, hot pressed silicon nitride, silicon oxynitride, sialon and their composites. Design of new generation radome materials was conceptualized and discussed as applicable to silicon nitride and related ceramics, wherein incorporation of varied degree of porosity improves electromagnetic properties, simultaneously, maintaining the required mechanical strength. Multilayer and graded porosity and its influence on electromagnetic properties were briefly discussed. Si3N4 ceramics having controlled porosity leading to optimum electromagnetic and mechanical properties produced through systematic processing is proposed as the futuristic high temperature radome material for supersonic applications. 相似文献
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Kishore Kumar Kandi Nagaveni Thallapalli Surya Prakash Rao Chilakalapalli 《International Journal of Applied Ceramic Technology》2015,12(5):909-920
Radome is an aerodynamic structural part attached to the fore‐end of a missile. It transmits electromagnetic signals with minimum attenuation and also protects radar communication system, and thus, the radomes are made of ceramics as they have desirable properties required by the radomes. The flexural strength, dielectric constant, and loss tangent values of various ceramic materials used in the development of radomes are important in the selection of radome materials. Different nose cone shapes of missile radomes are also important. Ceramic materials show variational properties with sintering time, temperature, and other additives. The existing different near‐net shape fabrication techniques for manufacturing of ceramic radomes are discussed and compared. Gelcasting is one of the manufacturing techniques to produce radomes with homogeneous and high green strength. Gelcast parts of silicon nitride ceramics are hard, tough, brittle, and wear‐resistant and are difficult to machine using conventional methods of machining. Therefore, laser‐assisted machining is used for fine finish of ceramic radomes with excellent surface integrity and productivity. This paper deals with a review of development of ceramic radomes, manufacturing methods for variety of applications. 相似文献
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微波加热技术因其绿色环保、体积加热、选择性加热等优势,已被广泛应用于化工强化、金属冶炼、陶瓷烧结、食品加工等众多领域,但微波在反应器内普遍存在透波效果差、微波利用率低等问题。随着微波加热技术的不断发展,微波加热设备中透波材料的选用越来越受到大家的关注。本文主要针对透波材料在微波加热领域中的应用现状进行综述,对透波材料的种类进行简要介绍,分别从微波加热用容器和保温材料两方面进行论述。详细介绍了氧化物、氮化物、硅酸盐、磷酸盐等高温透波材料及聚四氟乙烯、玻纤增强树脂基、环氧树脂等中、低温透波材料的研究进展,并具体论述了目前微波加热常用纤维棉、纤维毯和纤维板等各种陶瓷纤维制品的介电特性和透波性能,最后指出了目前微波加热用透波材料普遍存在的问题,并对透波材料的应用和发展作出了展望。 相似文献
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Dielectric and mechanical properties of hypersonic radome materials and metamaterial design: A review 总被引:1,自引:0,他引:1
《Journal of the European Ceramic Society》2022,42(1):1-17
This review paper examines ten current ceramic radome materials under research and development and provides a comprehensive overview of available high temperature and high frequency data from literature. An examination of metamaterials for radio-frequency transparent radomes is given and our preliminary experimental results of a high-temperature metamaterial design are presented. The next-generation hypersonic vehicles’ radome temperatures will exceed 1000℃ and speeds will exceed Mach 5. An ideal radome material will have a high flexural strength, low dielectric constant and loss tangent, and high resistance to thermal shock and corrosion. The microstructural effect on the dielectric and mechanical properties and the effects of environmental factors such as rain are discussed. The impact of metamaterial structure on key radome factors such as boresight error, gain, and polarization is examined. After examining the associated benefits with the use of metamaterials, our preliminary results for a potential high-temperature metamaterial design are presented. 相似文献
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介绍大型地面雷达天线阵列防护罩所用的材料及其制造工艺。首次采用低压共固化工艺成功地制造了大尺寸的A型夹层结构雷达罩。结果表明,所选用的材料和工艺可行,雷达罩的整体性能和尺寸精度均满足性能指标要求。 相似文献