The effect of fibre waviness on the mechanical properties of unidirectional fibre composites: A review

Abstract Four properties of unidirectional fibre composites are shown to be influenced by fibre waviness. Compressive strength (and also modulus) can be related to fibre waviness by relatively simple equations. Loss in strength during fatigue does not lend itself so easily to simple analysis, but seems to be readily explicable if the fibres are not straight. Shear strength parallel to the fibres is greater than the matrix shear strength—and at high temperatures much greater—and simple equations can be used to explain this in terms of fibre waviness. Finally, some features of delamination resistance can be explained in terms of fibre waviness. However, both for shear and delamination resistance, more data is needed on the degree of fibre waviness in test samples.