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Thermal expansion performance of Aluminum/polysiloxane/glass coatings with low infrared emissivity was improved by adding zinc powder. The influences of zinc powder on phase structure, composition, surface microstructure, thermal expansion, adhesion and infrared radiation of Aluminum/polysiloxane/glass coating was systematically studied. The thermal mechanical analysis indicated that thermal expansion coefficient can be adjusted by adding zinc powder in the coating. The tensile strength test results show that the matching of the thermal expansion could improve the adhesion strength of the coatings. As a result, compared with the coating without zinc powder, the adhesion strength was enhanced by 2.0 ± 0.4 MPa when the heat treatment temperature at 450 and 500 °C, and increased by 3.0 ± 0.4 MPa at 550 °C. Simultaneously, average infrared emissivity value of the coating with good thermal stability was about 0.20 in the 3–5 μm wavebands, and approximately 0.34 within 8–14 μm after heated at 550 °C. These results indicated that the good thermal expansion performance and low infrared emissivity coatings were obtained by adding zinc powder.

In this study, low infrared emissivity coatings with good thermal stabilities were fabricated using silicone resin as adhesive, flake aluminum powder as pigment, and low-melting glass powder as functional filler. The effects of the low-melting glass powder on the adhesions, thermal expansions, and infrared emissivity of the coatings were systematically investigated. In addition, the surface microstructures and thermal stability mechanisms of the coatings were analyzed in detail. Mechanical tests showed that the addition of the low-melting glass powder to the Al/polysiloxane coating enhanced its adhesion after a high-temperature treatment due to the mechanical interlocking of the particles by the secondary film-forming low-melting glass. Thermal analysis indicated that the oxidation resistance of the coating could be improved by the film-forming low-melting glass powder. The low-emissivity coating with a low-melting glass powder content of approximately 15 wt.% and Al/polysiloxane ratio of 1.5 exhibited good thermal stability. The adhesion of the coating increased to 9.0 ± 0.4 MPa after heating at 500 °C. When the content of the low-melting glass was increased from 0 to 15 wt.%, the oxidation exothermic peak of the coating shifted from 590 to 625 °C at a pigment/binder ratio of 1.5. The infrared emissivity of the coating was 0.25 after heating at 600 °C.