Kinetics of the α-β phase transformation in seeded Si 3N4 ceramics

Abstract

The α-β phase transformation in Si3N4 was studied for seeded samples using an Y2O3-Al 2O3 mixture as a sintering aid. The concentration of β-seeds varied from 0 to 5 wt.%. The results showed that α-β phase transformation followed the first-order reaction. The calculated activation energy for seeded samples was in the range from 348 to 378 KJ/mol, indicating boundary reaction as the rate limiting step.