Bending property of novel 3D woven variable thickness composites: Experiment and finite element analysis

Variable thickness composites are essential engineering materials which have been used in various high‐performance products. However, the commonly used variable thickness composites are mainly lamination, which is prone to delamination and reduce the overall performance under load. To solve this problem, 3D woven fabrics with integrity and continuous variable thickness have been designed and weaved on ordinary looms using basalt yarns. The resin‐based variable thickness composites have been prepared by vacuum‐assisted resin transfer molding (VARTM) process, and two different laminated composites have been produced for comparison. Compared with the two kinds of laminations, the bending strength of the 3D woven variable thickness (3DWVT) composites is increased by 12.28% and 16.22% under positive load; 16.74% and 17.08% under negative load. Finally, the meso‐finite element simulation analysis of the bending performance of 3DWVT composites was carried out by using the meso‐finite element analysis (FEA), and the damage mechanism and failure mode were explored. Schematic diagram of bending property and FEA of novel 3D variable thickness composites.