Phase characterization in Si3N4-SiC particulate composites performed by EELS in a 1 MV microscope

Abstract

Abstract The purpose of this work was to determine the origin of the influence of SiC on the Si3N4 grain growth in Si3N4-SiC particulate composites. Materials containing either 17 wt% or 34 wt% of SiC were analysed by electron energy-loss spectroscopy (EELS) in a 1 MV microscope. The typical EELS spectra of the different constituents were obtained. They included plasmon distribution and inner-shell excitation edges. The distribution of SiC grains in the composite was determined. A qualitative analysis of the intergranular phase was performed which demonstrates that dissolution-precipitation in the liquid oxide phase of both SiC and Si3N4 occurs during the sintering and thus influences the Si3N4 grain growth.