Published online by Cambridge University Press: 22 February 2011
The microstructure of the interfacial zone in a SCS6 filaments/Ti-6A1–4V matrix composite was determined using TEM and HREM. The interfacial zone (e ∼5 μm) consists of microstructurally distinct layers. The fiber/matrix interaction resulted in two layers respectively crystallized in grains of about 20 nm and 100 nm. The reaction zones are mainly made of brittle TiC. They are separated from the SiC reinforcement by five layers which form the coating of the SCS6 filament. These five layers may be described as SiC-C composites with either an equiaxe fine grain structure or a distorted lamellar structure. The structure of these layers can explain the toughning of the alloy by the SCS6 filaments despite of the brittle F/M reaction products formed during the processing.