A method for preparing ultrafine composite particles of aluminum nitride and rare earth nitride

摘要

Ultrafine particles of aluminum nitride having a morphologically anisotropic structure of columns, plates, or whiskers such that the ratio of thickness or width to length or the ratio of thickness to width or length of particle is not less than 1 are produced by thermally melting a binary alloy of metallic aluminum and a rare earth element in a nitriding atmosphere containing nitrogen. By this method are produced composite ultrafine particles which substantially comprise ultrafine particles of aluminum nitride having the morphologically anisotropic structure and ultrafine particles of the rare earth nitride which functions as a sintering auxiliary therefor. The composite ultrafine particles or an aggregate thereof are usable as a raw material for the production of a sintered article, a reinforcing material for various metal-based composite materials, a blast powder, and the like.