Improved ablation resistance of C–C composites using zirconium diboride and boron carbide

Abstract Zirconium diboride and boron carbide particles were used to improve the ablation resistance of carbon–carbon (C–C) composites at high temperature (1500 °C). Our approach combines using a precursor to ZrB 2 and processing them with B 4 C particles as filler material within the C–C composite. An oxyacetylene torch test facility was used to determine ablation rates for carbon black, B 4 C, and ZrB 2 –B 4 C filled C–C composites from 800 to 1500 °C. Ablation rates decreased by 30% when C–C composites were filled with a combination of ZrB 2 –B 4 C particles over carbon black and B 4 C filled C–C composites. We also investigated using a sol–gel precursor method as an alternative processing route to incorporate ZrB 2 particles within C–C composites. We successfully converted ZrB 2 particles within C–C composites at relatively low temperatures (1200 °C). Our ablation results suggest that a combination of ZrB 2 –B 4 C particles is effective in inhibiting the oxidation of C–C composites at temperatures greater than 1500 °C.