Construction of 3D aluminum flake framework by sponge template to prepare thermally conductive polymer composites

Ceramic-based polymer composites with high thermal conductivity and electrically insulation has been wildly used in modern electrical systems for thermal management application. Compared with ceramic materials, metals usually exhibit better...

Chemical Extractive Technique for Commercial Purity Metals

Commercial purity iron powders were produced by using a new hydrometallurgy process. It was found that the most important factor in enhancing the purity of iron was the number of water washing process. X-ray diffraction pattern showed that the high peak purity of iron powder increased with increasing the number of water washing. The developed new methodology was based on the reaction between the aqueous ferrous sulfate and the hydrochloric acid with the presence of high purity aluminum flake. The purity of iron powders increased considerably with increasing the multi-water washing for leachate containing iron powders. The purity of iron powders was reached up to approximately 93.5%. The mean particle size distribution and apparent density for the highest value of purity are 50-100 µm and 2.85 g/cm3 respectively.

Synthesis and Characterization of Magnetic Al/NiO Composite Pigments with Low Infrared Emissivity

Generally, traditional low infrared coatings based on metallic pigments cannot have low lightness, low infrared emissivity and low radar reflectivity simultaneously. Herein, we used a simple and efficient method to synthesize magnetic Al/NiO composite pigments which possessed all these attributes to a degree. The results indicated that the covering area of NiO on the aluminum flake could be tuned by the addition amount of NiCO3 and the reaction temperature of hot-flowing, both of which played a key role on the VIS/IR spectral reflectance and magnetic properties. The magnetic Al/NiO composite pigments with low lightness and low infrared emissivity could be obtained at 130 °C for 24 h in hot flowing liquid. The lightness L* could be decreased to 75.94, however the infrared emissivity (8-14 μm) was also low to 0.421. Compared with the single aluminum flakes, the Al/NiO magnetic composite pigments presented stronger magnetic properties. Therefore, the Al/NiO magnetic composite pigments offered a new choice for the pigments of multispectral stealth coating.