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Zirconium carbide (ZrC) coatings were fabricated by chemical vapor deposition (CVD) using ZrCl4, CH4/C3H6, and H2 as precursors. Both thermodynamic calculation results and the film compositions at different temperatures indicated that zirconium and carbon deposited separately during the CVD process. The ZrC deposition rates were measured for CH4 or C3H6 as carbon sources at different temperatures based on coating thickness. The activation energies for ZrC deposition demonstrated that the CVD ZrC process is controlled by the carbon deposition. This is also proven by the morphologies of ZrC coatings.

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Polysiloxanes polymer coatings were formed on carbon fiber‐reinforced silicon carbide (C/SiC) composites at 100°C in air with barium–strontium aluminosilicate (BSAS) as fillers. After the polymeric coatings were pyrolyzed at 1350°C under argon, a dense SiOC–BSAS‐coated C/SiC composite was obtained. The oxidation test in dry air and the corrosion test in water vapor were carried out on the coated composites at 1250°C, respectively. The results indicated that the polymer‐derived SiOC–BSAS coatings could protect the C/SiC composites well both in dry air and water vapor. Even after corroded for 200 h in water vapor, the coated C/SiC composites showed little weight loss and high residual flexural strength.