Study of SiC-SiAlON Composite Formation by Nitridation of SiC-A162.5Si Mixture

摘要

SiC-SiAlON composite formation was achieved by means of nitridation in a furnace with graphite heating element. SiC and A162.5Si alloy powders with broad grain size distribution were used as raw materials. After mixing, the powders were compacted into cylindrical green bodies of 25mm diameter and 10 mm height by uniaxial pressing with subsequent cold isostatic pressing. Green densities of about 2.35 g/cm~3 were achieved. Nitridation was carried out in stagnant nitrogen atmosphere under normal pressure (0.1 MPa). Heating rate was 20deg.C/min up to 1000deg.C, and 10 characterized by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction.