A SiC/ZrB2–SiC/SiC oxidation resistance multilayer coating for carbon/carbon composites

To extend the oxidation protective temperature range of coating for carbon/carbon (C/C) composites, a SiC/ZrB2–SiC/SiC multilayer coating was prepared by a three-step method of pack cementation, slurry and chemical vapor deposition. The prepared coating is composed of three layers with about 150 μm in thickness. It can protect C/C composites from oxidation for more than 300 h at 1173 K which is attributed to the oxidation ability of ZrB2. The coating can also effectively protect C/C composites from oxidation at 1773 K for 217 h which is due to the SiO2–ZrSiO4 compound glass during oxidation test.

► A SiC/ZrB2–SiC/SiC multilayer coating was prepared to extend oxidation protective temperature range for C/C composites.
► The coating can protect C/C composites from oxidation for more than 300 h at 1173 K and 217 h at 1773 K.
► The oxidation resistance at 1173 K is attributed to the oxidation ability of ZrB2.
► The formation of SiO2–ZrSiO4 compound glass provides oxidation protection for coated C/C composites.