Carbon/SiC Hybrid Bonding between Carbon-Carbon Composites

Abstract

In order to use carbon/carbon composites (C/Cs) in various hot structures, a bonding technique effective at elevated temperatures is frequently required. In the present study, a hybrid bonding technique suitable for C/Cs is proposed. This hybrid bonding involves carbon bonding followed by the infiltration of molten Si into cracks in the carbon bonding-layer. During and after the infiltration, Si was converted to SiC by a chemical reaction with carbon in the bonding layer and the substrates. Thus, the resulting bond was nearly crack-free and exhibited much higher strength than carbon bonds. The bonding strength of the hybrid bond was then evaluated at temperatures up to 2273K in a vacuum, and was compared with the bonding strength of carbon or SiC bonds. These results demonstrated that the hybrid bonding technique, unlike carbon and SiC bonding, has the advantage of simultaneously providing high strength and easy processing.