Abstract
A monotonic tensile test and a loading-unloading test are performed to investigate matrix crack initiation and growth in CFRP angle-ply laminates. A material used is T300/2500 carbon/epoxy system. Laminate configuration is［±45]s. During the tests, the polished edge surface of the specimens are examined by using the replica technique. The matrix densities in ＋45°and －45°plies are measured as a function of the laminate strain. To discuss the experimental resutls, the shear-lag analysis is used to obtain the stress fields in angle-ply laminates with matrix cracks. The Young's modulus reduction and change in Poisson's ratio due to matrix cracking is predicted and compared with the experimental results.
