Effect of the fiber cut angle on the shearing strength of unidirectional and cross-ply carbon-fiber-reinforced thermoplastic laminates

This paper quantitatively clarifies the effect of the fiber cut angle on the shearing strength of carbon-fiber-reinforced thermoplastic laminates. First, the shearing strength of the unidirectional and cross-ply laminates was measured at various cut angles. Next, two mechanics models, a rule-of-mixture-based model and a failure criterion model, were established to predict the shearing strength of the unidirectional and cross-ply laminates. The rule-of-mixture model explains the effect of the cut angle on the shearing strength of the unidirectional laminate. The failure criterion model predicts the dependence of the cut angle on the shearing strength for both laminates. Finally, finite element analysis was performed to semi-quantitatively evaluate the assistance effect of bending stress. It was revealed that the effective bending stress is almost equivalent to the stress averaged over approximately the one-layer thickness from the surface.