The fatigue behaviour of Kevlar fibre-reinforced composites is a subject not often studied and requires a better understanding. The objective of this study is to characterize the fatigue strength of a Kevlar/epoxy laminate composite as well as the benefits obtained using a nanoclay-filled epoxy matrix. The filler used was an organoclay Cloisite 30B after applying an appropriate silane treatment and other proprietary chemicals to improve the dispersion and interface adhesion. Twelve ply laminates, all in the same direction, of woven bidirectional Kevlar 292, were prepared by hand lay-up, using an SR 1500 epoxy resin. The composite sheets were produced by a vacuum moulding process. The addition of nanoclays reduced static strength and increased the stiffness in both tension and bend loading. Filled composites exhibited tensile fatigue strengths 12% higher than unfilled matrices, but in three-point bending the fatigue strength of filled composites was lower.
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