Semiquantitative IR method for determining phase composition of ultradisperse powders of Si <inf>3</inf> N <inf>4</inf>⁺

Abstract

An IR method was used for determining phase composition of nine samples of ultradisperse powders (UDP) of Si 3 N 4 which have been synthesized by plasmachemical procedure. In samples taken from the filter (α + β)Si 3 N 4 completely prevailed, while in samples taken from the plasma aggregate walls there was 33-42% of unreacted Si. The high correlation of the obtained results was established in relation to the phase analysis results of the examined samples obtained on the basis of X-ray structural analysis, and to physico-chemical characteristics of powders (specific surface (S), particle diameter (d) and chemical analysis). © 1999 Akadémiai Kiadó.