Abstract:Multilayer SiC/C composites were fabricated by tape casting and hot pressed sintering.The SiC layers and the graphite layers were found to be aligned alternately and reasonably uniformly and their interfaces were straight and well distinguishable. Mechanical properties were measured and the results showed that the strength of multilayer SiC/C composites was slighhtly less than, while its fracture toughness was higher than that of monolithic SiC. Multilayer SiC/C composites revealed a saw tooth load displacement curve. This was different from catastrophic fracture curve for monolithic SiC, and similar to the theoretical curve. Cracks propagated through multilayer SiC/C composites mainly along a step like paths, accompanied by crack branching, crack parallel propagation. Whisker like microcracks and cracks being absorbed at the weak interface were also observed by SEM. The toughening mechanism in multilayer SiC/C composites was attributed to a combination of all these effects.