SiC-MoSi2-(Ti0.8Mo0.2)Si2 multi-composition coating for carbon/carbon composites

To protect carbon/carbon (C/C) composites from oxidation, a new type of oxidation protective coating has been produced by a pack cementation technique in an argon atmosphere. XRD and SEM analysis showed that the phases of the composite coating were composed of SiC, MoSi2, and (Ti0.8Mo0.2)Si-2. Oxidation test discovered that the weight loss of the SiC coated C/C was up to 11.26% after 5 h oxidation in air at 1773 K and the weight loss of the SiC-MoSi2-(Ti0.8Mo0.2)Si-2 coated C/C composites characterized by excellent thermal shock resistance was only 2.18% in the same condition for 49 h. The oxidation of the coated C/C composites was primarily due to the reaction of the C/C matrix and oxygen diffusing through the penetrable cracks in the coating. (c) 2006 Elsevier B.V. All rights reserved.