Substitution of Y 2O 3 by a rare earth oxide mixture as sintering additive of Si 3N 4 ceramics

Abstract

The objective of this work was to compare the sinterability, the microstructures and the mechanical properties of Si 3N 4 ceramics with additive mixtures based on yttrium oxide, Y 2O 3, and a mixed concentrate of yttrium and rare earth oxides. The RE 2O 3 samples were prepared by a two-step gas-pressure sintering process. No significant differences between the samples have been found, thus demonstrating the potential of this low cost alternative sinter additive.