A MoSi2/SiC oxidation protective coating for carbon/carbon composites

To protect carbon/carbon (C/C) composites against oxidation, a MoSi2 outer coating was prepared on pack-cementation SiC coated C/C composites by a hydrothermal electrophoretic deposition. The phase composition, microstructure and oxidation resistance of the prepared MoSi2/SiC coatings were investigated. Results show that hydrothermal electrophoretic deposition is an effective route to achieve crack-free MoSi2 outer coatings. The MoSi2/SiC coating can protect C/C composites from oxidation at 1773 K for 346 h with a weight loss of 2.49 mg cm−2 and at 1903 K for 88 h with a weight loss of 5.68 mg cm−2.

Research highlights
► A crack-free MoSi2 outer layer was deposited on SiC pre-coated C/C composites by a novel hydrothermal electrophoretic deposition under an optimized condition.
► The prepared MoSi2/SiC multilayer coatings exhibit excellent oxidation resistance.
► The oxidation activation energy of the coated sample is calculated to be 120.96 and 82.41 kJ mol−1 for the temperature range of 1623–1881 and 1881–1923 K, respectively.