Microstructure of capacitor discharge joined SiAlON and silicon nitride ceramics

Abstract

Silicon nitride based ceramics offer great potential for industrial applications. However, the joining of Si3N4 based materials is necessary in various applications and this can be difficult to achieve. A capacitor discharge joining technique was used successfully to join oxide ceramics using thin metal foil interlayers. In this work, silicon nitride and SiAlON ceramic joints were produced using Ti thin foils interlayers. The bond strengths of the resulting joints were assessed by shear testing and their interfacial microstructures were examined by a scanning electron microscope (SEM) with an attached energy dispersive x-ray spectrometer (EDX). Line scan analyses showed that Ti diffuses into the ceramic parts while Si and Al diffuse into the Ti interlayer.