Heat-treated sandwich structures of borosilicate glass and 6H-SiC single crystals (with and without platinum pre-coating) were used as model composites to study the reaction kinetics of the interlayer formation in the system Si-C-O. High resolution and analytical electron microscopical methods revealed a complex interlayer system, mainly consisting of different phases of carbon and silica. A distinct increase in the degree of graphitisation and texturisation of the reaction layer was observed after Pt deposition on the silicon carbide surface, which is attributed to the graphitising effect of both platinum and platinum silicide. (C) 2003 Elsevier B.V. All rights reserved.