Preparation and properties of Al/Bi ₂O ₃ composite particles with medium-low infrared emissivity for infrared camouflage

Better coated Al/Bi ₂O ₃ composite particles were prepared using bismuth nitrate and flaky aluminum powders as raw materials by co-precipitation method though the recombination of Bi ₂O ₃ on the surface of flaky aluminum powders. In order to obtain a better IR camouflage performance, the morphologies, phase composition were characterized by SEM, XRD and IR. The infrared emissivity of Al/Bi ₂O ₃ composite particles was tested by infrared emissivity instrument. The results showed that the infrared emissivity of composite particles with yellow body color sintered under temperature 450°C was 0.73. The precursors were produced under precipitating temperature 50°C for 2 h. The sheet aluminum powders were coated by Bi ₂O ₃, then their color became yellow. They could avoid the "betray oneself", oxidation and provide an excellent material for infrared stealth camouflage.