HfC/ZrC ablation protective coating for carbon/carbon composites

HfC/ZrC coatings were co-deposited on carbon/carbon composites by chemical vapor deposition using a gas mixture of HfCl4, ZrCl4, CH4, H-2 and Ar. The phase composition, microstructure, growth behavior and ablation performance of the HfC/ZrC coatings are investigated. Results show that the as-prepared coatings are biphasic coating consisting of HfC and ZrC. The methane concentration plays a significant part in determining the internal structure, growth behavior and then the ablation performance of the HfC/ZrC coatings. The biphasic coating cans protect C/C composites through consuming the oxidized gases and isolating the substrate from ablation environment. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.