Abstract

We have determined all five independent elastic-stiffness coefficients C ij of a silicon carbide fibre with transverse isotropy from room temperature up to 873 K. Firstly, we measured the C ij of a titanium-alloy-matrix composite reinforced unidirectionally with the fibres and the matrix alloy alone. Electromagnetic acoustic resonance detected the free-vibration resonance frequencies of the specimens to determine their C ij . Secondly, we applied a micromechanics calculation to deduce the fibre C ij from the measured composite and matrix C ij . The resulting fibre C ij shows strong anisotropy in the temperature derivatives of the C ij ; the temperature derivatives for the fibre-axis-direction C ij are much smaller than the others