High-temperature-resistant coatings with low infrared emissivity were prepared using polysiloxane resin and flake aluminum as the adhesive and pigment, respectively. The heat resistance mechanisms of the polysiloxane/Al coating were systematically investigated. The composition, surface morphology, infrared reflectance spectra, and thermal expansion dimension (ΔL) of the coatings were characterized by X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy, and thermal mechanical analysis (TMA), respectively. The results show that thermal decomposition of the resin and mismatch of ΔL between the coating and the substrate facilitate the high temperature failure of the coating. A suitable amount of flake aluminum pigments could restrain the thermal decomposition of the resin and could increase the match degree of ΔL between the coating and substrate, leading to an enhanced thermal resistance of the coating. Our results find that a coating with a pigment to binder ratio (P/B ratio) of 1.0 could maintain integrity until 600 °C, and the infrared emissivity was as low as 0.27. Hence, a coating with high-temperature resistance and low emissivity was obtained. Such coatings can be used for infrared stealth technology or energy savings in high-temperature equipment.

A design method of five-band polarization-insensitive metamaterial absorber (MMA) based on the slotted structures and the magnetic rubber is proposed for L-, S-, C-, X-, and Ku-band applications. The slotted structures of the top layer, which evolved from two square rings, are used to excite multi-resonance. The range of the electromagnetic (EM) parameters of a magnetic rubber substrate, which is used to adjust the equivalent impedance of the absorber to match the free space impedance in different bands, is estimated using the impedance matching principle. A series of magnetic rubber substrates based on the estimated EM parameters are prepared and measured, whose thickness is only 0.7 mm, meeting the thin design requirements. The absorption of the proposed absorber greater than 90% at 1.7 GHz, 3.87 GHz, 5.96 GHz, 9.4–10.4 GHz, and 14 GHz is achieved when the doping amount of the carbonyl iron powders is 200%. The absorbing performance of the absorber with measured EM parameter agrees well with the theoretical estimates, which validates the accuracy of the proposed design method.

Al and Al/Ni bilayer films were prepared by magnetron sputtering and evaluated as functional coatings for aerospace thermal-control applications. The effects of sputtering time and power on the structural, electrical, magnetic, and infrared optical properties were systematically investigated. The resistivity of Al films decreased with increasing sputtering time and power, approaching a stable value at a deposition time of 20 min. Compared with single-layer Al films, the Al/Ni bilayer films exhibited compact morphology, good interfacial adhesion, improved infrared reflectance, and combined electrical conductivity with soft magnetic properties. When the sputtering time of the Al underlayer reached 20 min or longer, the infrared reflectance of the bilayer films remained above 95% in the 8–14 μm atmospheric window. These results indicate that magnetron-sputtered Al/Ni bilayer films are promising lightweight multifunctional coatings for aerospace thermal management and infrared shielding.

In this paper, radiation spectrum design methods of material were proposed. Effect of temperature and atmospheric transmission on the infrared radiation transmission of materials was studied. The radiation properties of different materials were analyzed at different temperature. The transmission of aircraft surface materials infrared radiation was studied, according to the environment and the radiation transmission. Moreover, the spectrum of the two materials with the consistent emissivity was studied. Material has less radiation characteristic peak within the 3.0−4.3 μm and low radiation intensity within the 8−14 μm, which has good spectral stealth properties at 250−450 K. The radiation spectrum peak of the material was not obvious within the 4.3−8.0 μm owing to the low transmittance of atmosphere. In conclusion, research results have good significance for the spectral stealth design of materials, and can potentially be used in infrared spectral stealth technology and equipment.