ABSTRACT
Dense Si3N4/SiC (10, 15, 20 and 25 weight%) composites were prepared by hot-isostatic-pressing after gas pressure sintering, using commercially available silicon carbide powder with the average particle size of 0.3 μm. The grain growth of β silicon nitride during the densification was suppressed by the addition of SiC. As the result, the microstructure became finer and the flexure strength was improved. However, the strengths of the Si3N4/SiC composites and the Si3N4 monolith began to deteriorate at a same temperature and the creep strain of the Si3N4/SiC composite was larger than that of the Si3N4 monolith. In this study, it was concluded that the addition of SiC is effective for the flexure strength improvement but not for the heat resistance.
