Nonuniform Densification during Gas Pressure Sintering of an alpha-Sialon Ceramic

Densification of α‐sialon ceramics during gas pressure intering was investigated experimentally. The densification did not occur uniformly throughout specimen compacts. Instead, it started at the surface and progressed into the interior of the compacts. The kinetics of this unique nonuniform densification was strongly influenced by the applied N2 pressure. The nonuniform densification behavior was attributed to the slow diffusion‐out of N2 gas entrapped in pores.