Experimental Study of Mechanical Behavior of 3D Angle-Interlock Woven Fabrics under Cyclic Load

During the formation of complex shapes, textile reinforcement is subjected to large local and global deformation, which affects the quality of the final composite product. This study investigated the deformation behaviors of 3D angle-interlock woven fabrics, which were used in their "dry state". Hence, both cyclic tensile tests and picture-frame type of shear tests were performed to compare the deformation processes. The results showed that the shear cyclic displacement condition produced a higher shape-preserving ability than its tensile counterpart. In addition, the negative Poisson’s ratio in the thickness direction was observed only when the tensile displacement was applied along the warp direction. A theoretical model was presented to predict the thickness variations of the woven fabrics and the results agreed well with the experiments.