Abstract: The nanosized chromium oxide powders were synthesized by the precipitation method. Then they were nitrided by NH₃ at 800-900℃ for 4-8h, and 40-80nm
chromium nitride powders obtained. X-ray powder diffraction and TEM were adopted for the characterization of the powders obtained under different ammonolysis
conditions. The influences of the ammonolysis temperature and the holding time on the powder properties were investigated. The results show that this process
for preparing CrN powders possesses many advantages such as time saving, temperature lowering, and simpler equipment needed.

Key words: ammonolysis, .chromium nitride, nanocrystalline powders