Ablation behavior and high temperature ceramization mechanism of TiB2-B4C-ZrC modified carbon fiber/boron phenolic resin composites

Abstract

The carbon fiber (CF) reinforced boron phenolic resin (BPR) matrix composite, renowned for its exceptional ablation resistance, represents a promising material for high-temperature applications. However, hypersonic vehicles are subjected to increasingly challenging service environments, which necessitate materials capable of enduring even more extreme temperatures. Consequently, there is a growing need for composites that exhibit superior ablation resistance. To tackle these demanding requirements, this research initiative introduces the integration of ceramizable fillers, including TiB2, B4C, and ZrC, into the composite structure to create a high-temperature ceramizable system. The experimental findings indicate that the composites formulated with this innovative system demonstrate extraordinary ablation resistance, even when exposed to oxyacetylene flames with a heat flux of 4364 kW/m2. Notably, the measured linear ablation rate and mass ablation rate were recorded at −0.012 mm/s and 0.0268 g/s, respectively. These values are exceptionally low. Subsequent analysis utilizing X-ray diffraction (XRD) and additional characterization techniques has confirmed the formation of a dense ceramic layer with a B-C-O-Ti-Zr composition on the composite surface at elevated temperatures. This ceramic layer acts as a formidable barrier, significantly mitigating the ablation effects caused by high-temperature exposure. Meanwhile, it is pertinent to note that the formation of the ceramic layer is accompanied by an endothermic reaction, which consequently leads to a reduction in the thermal conduction of the composite to some extent.