Initial failure maps for ceramic and metal matrix composite laminates

Initial failure maps define damage-free loading regions in the laminate stress space, such that local stresses in the individual phases and interfaces in each ply do not exceed specified strength magnitudes. The maps are constructed here for several symmetric laminates and composite systems loaded by uniform membrane stresses. The (0/+/-45)(s) layup was selected for the Al2O3/MoSi2 and SCS-6/Ti3Al systems, and the (0/+/-45/90)(s) layup for the SCS-6/Timetal-21S composite. Results are presented both in the S11S22 and S11S12 stress planes, where the x(1)-axis coincides with the zero-degree fibre direction. Residual stress effects induced by fabrication and/or thermal changes are included.