The mechanical behaviour of a C/SiC material, infiltrated by liquid silicon, was investigated. Structural features have been attributed to the damage and failure behaviour of the material. The material can be described by a two-component model : the fibre bundles in the loading direction (component 1), and the rest of structure (component 2). The fibre bundles in the loading direction largely determine the deformation and failure behaviour, whereas the rest of the structure essentially determines the damage behaviour of the material. The structural features do not undergo changes up to 1400 degrees C in mechanical tests, whereas the mechanical properties undergo slight changes. Heat treatment of the material at elevated temperatures causes a change in the structural features and leads to a reduction in strength and in interlaminar shear strength.