Thin-ply composite laminates: a review

Composite structures formed using thin-ply laminates are of interest to aerospace and other high-performance industries. This paper reviews recently published research into fibre reinforced polymer matrix composites formed using thin-ply (< 100 mu m thick) laminates. Due to their prominence in the literature, this review focuses on thin plies formed with carbon fibre tows. Research into the manufacture, microstructure, mechanical performance and implications for structural design are described. The benefits of thin plies compared with standard plies (similar to 125 mu m thick) are assessed, including flexibility in design, damage tolerance and potential for creating pseudo-ductile composite structures. Improvements to static and fatigue properties are discussed. The adverse effects of thin-ply polymer matrix composites are evaluated, including open-hole and notch sensitivity, as well as interlaminar fracture toughness. The underlying physical mechanisms responsible for the benefits and drawbacks of thin-ply composite laminates are described. One critical physical attribute of thin plies is found to be the relatively few number of fibres per ply, which allows for more variation in ply angle orientation compared with a laminate of the same thickness made with standard plies. Potential areas for further research are discussed, including processing techniques, joining, material hybrids, thermoplastics, durability, recyclability and applications to multifunctional composite structures.