Influence of Powder Properties and Green Microstructure on the Sintering Behavior of Si₃N₄

Abstract

Powder properties of raw materials have a great influence on the dispersion of sintering aids, and green microstructure and sintering behavior on the preparation of Si₃N₄ ceramics. The mixing time required for sufficient dispersion of the raw material powders in a suspension increased with decreasing particle size of Si₃N₄. For sintering below 1700°C, the relative density of sintered bodies was quantitatively related with specific surface area of Si₃N₄ powders and the mode pyre size in green compacts. Decrease of pore diameter in green compacts and particle diameter of Si₃N₄ powders improved the densification of Si₃N₄ ceramics at relatively low temperatures.