Effect of the Addition of Short Carbon Fiber on Thermal Insulation Properties of ZrB₂- SiC Hot-Pressed Ceramics

Abstract

Short carbon fibers reinforced ZrB2-SiC ceramics were prepared by hot pressing sintering process. The short carbon fibers with different volume fractions (0.2.4.6.8.10.20) were added for improving the thermal insulation properties of ZrB2-SiC ceramics. The experimental results showed that as the content of short carbon fiber increased, the thermal diffusivity decreased from 43.9m2/s to 32.9m2/s, the thermal conductivity decreased from 104.3 W/(m·K) to 72.9 W/(m·K) and thermal insulation performance reduced by 43.1%, respectively. The enhancement of the thermal insulation properties is mainly due to high interfacial thermal resistance of short carbon fiber and matrix.