抄録
The A15052/AFRP laminates often suffer from the cyclic bending moment of variable amplitude during the service. Thus the fatigue crack initiation would occur and propagate in the aluminum layer of laminate by the cyclic bending moment. The fatigue crack propagation in aluminum layer of A15052/AFRP laminate is commensurated with the delamination between aluminum layer and fiber layer. The delamination deteriorates the fiber bridging behind the crack tip of laminate. Therefore the influence of variable cyclic bending moment on the delamination and the fatigue crack propagation behavior in A15052/AFRP laminate need to be investigated. In this study, A15052/AFRP laminate composite of three thin sheets of A15052 and two layers of unidirectional aramid fibers was prepared and tested. The shape and size of the delamination zone formed along the fatigue crack between A15052 sheet and aramid fiber-adhesive layer behind the crack tip were measured by an ultrasonic C-scan. The relationships among da/dN, ΔK, the cyclic bending moment and the delamination zone size were studied.
