Influence of boron ion implantation on the oxidation behavior of CVD-SiC coated carbon-carbon composites

Abstract Two-dimensional carbon-fiber reinforced carbon-carbon (C/C) composites were implanted with boron ions with 70–360 keV energy, then annealed in an argon atmosphere at 1550°C, and finally coated with a CVD-SiC coating of 50 μm. Isothermal and cyclic oxidation tests were performed on the CVD-SiC coated C/C composites in flowing dry air at 1300°C. The CVD-SiC coated C/C composites with boron ion implantation exhibited largely lower weight loss than those with a direct SiC coating. A thin boron carbide layer was formed in the surface region of the C/C composites by boron ion implantation. This boron carbide layer was found to contribute to enhancing the oxidation resistance of the CVD-SiC coated C/C composites.