Mullite-Al2O3 -SiC anti-oxidation coating for carbon/carbon composites

摘要

In order to exert the unique high temperature mechanical properties of carbon/carbon composites, a new type of oxidation protection coating was firstly produced by two-step pack cementation technique in an argon atmosphere. XRD analysis showed that the internal coating obtained from the first step was gradient SiC layer which acts as bonding and buffering layer, and the multi-coating formed in the second step was Al2O3-mullite layer. It was found that the as-received coating characterized by excellent thermal shock resistance on C/C, exposures to an oxidizing atmosphere at 1600°C, could effectively protect the carbon/carbon composites from oxidation for 45 hours.