YE Fei, PAN Liji, LIU Ya, GUO Lucun

(College of Materials Science and Engineering, Nanjing University of Technology, Nanjing Jiangsu 21000, China)

Abstract:Light quality and high strength Si3N4/SiC materials were fabricated by reaction sintering. The effect of the firing system on Si3N4 phase was analyzed, and the effect of Si3N4 phase and the SiC aggregate size and gradation on the properties of samples were researched. The composition of phase and the microstructure of samples were characterized respectively by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the bulk density and mechanical properties were characterized respectively by Archimedes method and universal test machine. The experimental results show that the bulk density of the samples were increased and the bending strength of the samples were reduced by the adding of the large size SiC(D50=150μm). The increasing weight of samples were reduced and the nitride reactions were blocked when the large size SiC added to the samples.

Key words:silicon nitride; silicon carbide; reaction sintering; light quality; high strength