Preparation and properties of a porous ZrO2/SiZrBOC ceramic matrix composite with high temperature resistance and low thermal conductivity

Abstract

In this study, porous ZrO2/SiZrBOC and SiZrBOC ceramic matrix composites were produced via vacuum impregnation method, using SiZrBOC ceramic precursor as a matrix, ZrO2 fiber prepared via electrospinning as the reinforcing agent and polyurethane foam as a skeleton. Polyurethane foam with open porosity is rather a substrate for the creation of a skeletal 3D structure. The preparation process and pyrolysis mechanism of ZrO2/SiZrBOC polyurethane foam impregnated with a precursor solution were expounded. The thermal conductivity tests and mechanical property measurements show that the lowest thermal conductivity (0.0378 W m−1 K−1) was achieved in the ZrO2/SiZrBOC ceramic matrix composite at the pyrolysis temperature of 800 ℃, being much inferior to that of the SiZrBOC composite (0.0861 W m−1 K−1). At 1400 ℃, the maximum compressive strength of the porous ZrO2/SiZrBOC ceramic matrix composites reached a value of 1.37 MPa, while that of the SiZrBOC composites was 0.22 MPa only. Therefore, the addition of ZrO2 fibers improved the compressive strength and thermal insulation properties of the composites.