Preparation and characterization of nanocrystalline chromium boride

Nanocrystalline chromium boride (CrB) powders were successfully synthesized at 600 C through a solid-state reaction. The synthesis was carried out in an autoclave by using CrCl3, Mg and MgB2 as the reactants. The X-ray powder diffraction pattern indicates the formation of orthorhombic CrB. Transmission electron microscopy image shows that typical CrB crystallites are composed of floss-like particles with less than 10 nm in diameter and about 50–100 nm in length. Thermogravimetric analysis revealed that the oxidation resistance for nanocrystalline CrB is much lower than that of bulk CrB.