Effect of crossing warp architecture on tear strength of 3D orthogonal woven T-shaped reinforcements

Abstract

T-shaped textile composites reinforced by two-dimensional laminates and simple forms of three-dimensional reinforcements are susceptible to tear failure and delamination at the junction. To address these issues and enhance the tear resistance of composite T-joints, 10 types of crossing warp architecture based on three-dimensional woven orthogonal structures were designed, manufactured and characterized with the aim of optimizing the reinforcement architecture. The assessment of the in-plane mechanical behavior was carried out by a tensile tear load applied to the two flanges of the T-shaped reinforcements. The employment of crossing warp architecture effectively enhanced stiffness, tensile strength, and failure strain. Resistance to the failure of the reinforcement was increased as more crossing warp yarns were employed. To further optimize the crossing warp architecture for reinforcement development, the internal and external crossing arrangements were compared. The new finding was regardless of the crossing warp proportions, the external crossing warp led to a higher resistance to the tear force for the reinforcement than the internal crossing warp. The stiffness and tensile strength of the external crossing warp reinforcements exhibited notable improvement, with a maximum increase of 49.1% and 31.1% respectively, compared with that of the internal warp crossing counterparts. The findings in this research will be useful in manufacturing composite T-joints to tailor the reinforcement architecture with different crossing proportions and arrangements for meeting the required mechanical properties.