A skin layer made of cured polysilazane and yttria stabilized zirconia for enhanced thermal protection of carbon fiber reinforced polymers (CFRPs)

Abstract

This study reported for the first time using cured preceramic polymer precursor and their composites as thermal protection layer for the carbon fiber reinforced polymer (CFRP). The fabricated composite skin consists of cured polysilazane (PSZ) and yttria stabilized zirconia (YSZ) as the reinforcements and has a low density of 1.67 g/cm3, which can be used for both aerospace and defense applications. The coated composite showed excellent bonding integrity at the interface between the composite skin and the CFRP substrate. Thermal studies revealed the cured PSZ has excellent thermal stability up to its cured temperatures. Using the 3ω method, the room temperature thermal conductivity of PSZ was measured as 0.17 ± 0.02 W/m·K along the through-thickness direction. Thermal conductance of the skin layer is around 940 W/m2·K, which is about 45% reduction in conductance compared to the CFRP. Thermal insulation test shows that the coated composite can be used up to 250 °C. Experiment results demonstrated the skin layer's effectiveness in protecting the CFRP in high-temperature environments.