FRACTURE-BEHAVIOR OF CONTINUOUS ALUMINA FIBER-REINFORCED EPOXY

This work investigates fracture behavior of a continuous alumina fiber (FP) reinforced epoxy under compression at two different temperatures . Effects of fiber orientation, stacking sequence, and temperature on failure mechanisms of the composite material are analyzed through a sc anning electron microscope (SEM). Fiber orientation is found to affect the failure mechanisms of the FP/epoxy. While the failure of the 0-de gree laminae is mainly caused by fiber breakage, that of the 90-degree s laminae by sheared epoxy matrix. The [0(2)/90(2)]s laminates not onl y have the combined failure modes of the 0-degree and 90-degrees lamin ae but also show fiber micro-buckling in the 0-degree plies and ply de lamination at the interfaces of the 0-degree and 90-degrees plies. Fai lure mechanisms are found to be different between the symmetric and an tisymmetric crossply laminates. In addition, the composites fractured at 77 K display more fiber-matrix debonding, smoother fractured surfac es of fiber and matrix, and cleaner ply delamination at the interfaces of the 0-degree and 90-degrees plies than the composites fractured at 295 K.