Abstract In this article, we present an enhanced metamaterial radar absorbing coating (MRAC) which possesses good electromagnetic absorption performance and ultra-thin thickness at high temperatures. The absorber is composed of radar EM absorbing coating and a layer of metamaterial. The metamaterial layer on the coating can enhance the absorption in two aspects. First, due to the coupling between the high permittivity coating and metamaterial layer, the impedance can match a smaller thickness better than a coating alone. Meanwhile, intense EM fields appear the surface of metamaterial pattern, which can also promote the absorption. The periodic pattern is made of special alloy which provides high temperature resistance quality. It is worth noting that the processing merely requires traditional plasma spraying, which ensures the practicability and feasibility. A 0.96 mm thick sample can achieve EM reflection loss below -5 dB at 800 °C over the whole X band. The experimental results are also consistent with the simulation, which successfully verifies the feasibility and proposes a competitive design for radar absorbing coatings (RAC).

中文翻译：

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超薄高温NiCrAlY合金超材料增强型吸波涂层

摘要 在本文中，我们提出了一种增强型超材料雷达吸波涂层（MRAC），该涂层在高温下具有良好的电磁吸收性能和超薄厚度。吸收体由雷达电磁波吸收涂层和一层超材料组成。涂层上的超材料层可以从两个方面增强吸收。首先，由于高介电常数涂层和超材料层之间的耦合，阻抗可以比单独的涂层更好地匹配更小的厚度。同时，在超材料图案表面出现强电磁场，也可以促进吸收。周期性花纹由特殊合金制成，具有耐高温质量。值得注意的是，加工只需要传统的等离子喷涂，保证了实用性和可行性。0.96 mm 厚的样品可以在 800 °C 下在整个 X 波段实现低于 -5 dB 的 EM 反射损耗。实验结果也与模拟一致，成功验证了可行性，并提出了一种具有竞争力的雷达吸波涂层（RAC）设计。