Preparation and Property of SiC/(ZrB_2-SiC/SiC)_4 Anti-oxidation Coatings for C_f/SiC Composites

A SiC/(ZrB2-SiC/SiC)4 coating was prepared by slurry painting and pulse CVD. The composition and structure of the coating were studied by using XRD,SEM and EDS analysis,then the anti-oxidation property of the coating was investigated. The results show that the thickness of obtained coating is about 100μm,ZrB2-SiC layer and Pulse CVD SiC layer are bonded to each other alternately. After oxidation at 1500℃ in air for 25h,the weight loss of the Pulse CVD coating is 5.1%,while weight gain of the SiC/(ZrB2-SiC/SiC)4 coating is about 2.5%. The SiC/(ZrB2-SiC/SiC)4 coating shows excellent anti-oxidation property.