Self-propagating high-temperature synthesis of ZrB2-B4C composites with the dispersed phase as hollow shells

Abstract

The formation of the microstructure of ZrB2-B4C ceramic composites produced by SHS pressing has been studied. It has been shown that the exothermic interaction in a mixture of Zr, B, and C powders gives an equilibrium SHS product containing ZrB2 as a dispersed phase and B4C – as a ceramic binder. The effect of the ceramic binder (B4C) content on the formation of the microstructure of SHS composites has been studied. It is shown, at content of B4C 10-20 wt% homogeneous SHS composites were formed consisting monolithic the ZrB2 particles with a size of 10-12 pm, and at content of B4C 20-40 wt% – hollow shells consisting of the ZrB2 particles.