Nanocrystalline powder could be synthesized by solid-state reaction using the mixture which was prepared by a high energy milling process in a bead mill for and nanocrystalline powders mixture. Effect of the milling time on the powder characteristic of the synthesized powder was investigated. Nanocrystalline with a particle size of 50 nm was obtained at . High tetragonal powder with a tetragonality(=c/a) of 1.009 and a specific surface area of was acquired after heat-treatment at for 2 h. High energy ball milling was effective in decreasing the reaction temperature and increasing the tetragonality.

• 류성수 | Ryu Sung-Soo