A modified dual-layer SiC oxidation protective coating for carbon/carbon composites prepared by one-step pack cementation

To improve the oxidation resistance of SiC coating produced by pack cementation for carbon/carbon composites, a modified SiC coating has been produced by one-step pack cementation by adding ferrocene in pack compositions. The as-received coating exhibited a dual-layer dense structure, and oxidation protective ability of SiC coating could be improved by introducing ferrocene. The modified coating could protect C/C composites from oxidation for more than 100 h at 1673 K in air. The weight loss of the coated C/C composites was considered to arise from deflection of penetrating cracks formed in outer layer from inner layer to C/C matrix.

Research highlights
► A dual-SiC coating was prepared by introducing ferrocene in pack cementation.
► The minute SiC grains and SiC nanowires could effectively tought the coating.
► The coating could protect C/C composites from oxidation over 100 h at 1673 K in air.