Simultaneous low reflection in near-infrared range and low emission in long-wave infrared properties of Al/Bi2O3 composites

In this work, flaky aluminum was coated with bismuth oxide to obtain low reflection in near-infrared range and low emission in long-wave infrared stealth material. The composites were prepared through coprecipitation method, characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), and measured by ultraviolet spectrophotometer and dual band infrared emissometer. The morphology and microstructure show that the flaky aluminum was coated by bismuth oxide nanoparticles. The optimal reaction temperature was 50 degrees C, and the optimized amount of Al was 20 wt%. Meanwhile, the infrared emissivity in 8-14 mu m infrared waveband range was 0.462 and the reflectivity was 39.1% at wavelength of 1.064 mu m. In addition, it could also achieve good thermal insulation in a thinner thickness. When the temperature of heating platform reached 100 degrees C, the temperature of the disk with 0.30 mm thickness was 26.9 degrees C which was only 2.7 degrees C higher than that of the disk with 0.94 mm thickness. It may shed light on a new material design orientation to obtain high performance infrared and laser compatible stealth materials.