Investigation of the Phase Composition and Analysis of the Properties of Sintered and Hot-Pressed Materials Based on Silicon Nitride

This research analyzes the methods for producing silicon nitride and the properties of initial powders. The main methods for obtaining materials based on silicon nitride are described. Liquid-phase sintering and hot pressing were used to develop dense materials based on silicon nitride. As a sintering additive, 3 - 10 wt.% and 5 - 20 wt.% of yttrium-aluminum garnet were used for hot-pressed and sintered materials, respectively. The mechanical properties (modulus of elasticity, bending strength, fracture resistance, and Vickers hardness) of sintered and hot-pressed materials have been studied. Maximum properties were obtained with sintered materials containing 15% oxides and hot-pressed materials containing 10% oxides.