... .5 Spherical Main features;nano-iron, ultra-fine iron powder prepared by a special process, the product particle size ... elements , and high antioxidant capacity, low sintering temperature, black powder, average particle size 30-80nm, purity 99.99%. High- ... carbon-coated metal powder can be used as high-performance millimeter-wave military stealth material, visible and infrared stealth materials, stealth ...