Preparation Method of High Toughened Silicon Carbide with Sialon Grain Boundary

摘要

PURPOSE: Provided is a preparation method of toughened silicon carbide forming sialon in the grain boundary phase by hot pressing sialon-added raw materials and thermal treating. Therefore, the resultant silicon carbide has improved creep-resistance and high temperature strength compared with conventional silicon carbide. CONSTITUTION: The preparation method is as follows: preparing granulated silicon carbide powder by adding 2mol% of sialon composition powder(9wt.% of y2O3 + 16wt.% of AlN + 75wt.% of Si3N4) to SiC powder(alpha-phase + beta-phase) with 0.45 micrometer of size, and mixing for 5hrs.; hot-pressing at 1850deg.C for 30min. under 50MPa of pressure; thermal treating at 1950deg.C for 5hrs.