Review on the Mechanical Properties of Natural Fibre Reinforced Polymer Composites for Aerofoil Applications

Natural fibre-reinforced polymer composites (NFRPCs) are emerging as sustainable, lightweight materials with significant potential for aerofoil applications in the aerospace industry. This review explores the mechanical properties of NFRPCs that incorporate natural fibres, resin matrices, and fillers, focusing on their tensile strength, flexural performance, impact resistance, and fatigue durability. Natural fibres, such as flax, jute, hemp, and Doum palm leaf, are evaluated for their structural benefits, while epoxy resin is highlighted as a preferred matrix due to its high adhesion and thermal stability. Fillers, including silica, calcium carbonate, and nano-clay, are discussed for their role in enhancing the composite’s strength, thermal properties, and impact resistance, making NFRPCs suitable for demanding aerofoil applications. Adding fillers further improves performance, particularly in terms of durability, stiffness, and environmental resistance, which are crucial for aerofoil structures. The review also examines variability in natural fibre properties and presents strategies to address these issues through fibre treatments and hybridization techniques. Less research has focused on combining multiple natural fibres with fillers to create hybrid composites, which have shown promising mechanical enhancements in existing studies. Future directions are suggested to optimize NFRPCs for aerospace applications by using epoxy resin for improving fibre-matrix bonding. The review underscores the potential of NFRPCs as a sustainable and high-performance material solution for lightweight aerofoil structures in aerospace. Further investigation into innovative filler-natural fibre combinations, such as Calcium Sulphate Hemihydrate (CaSO₄·½H₂O) and Doum leaf stalk composites, could unlock new opportunities in aerospace and engineering fields.