Compression performance of integrated stitched sandwich structure composites

New type of integrated stitch sandwich structure was designed. The integrated stitched sandwich structure composites were prepared by vacuum infusion molding process (VIMP) to investigate the mechanical performance and failure mode under the flatwise compression load. Finite element model was established to study the effects of the stitching yarn consumption on flatwise compression mechanical properties of integrated stitched sandwich structure composites. The results indicate that the new type of integrated stitch sandwich structure composites can improve the number of yarns and avoid the disadvantages of fiber cross damage caused by the traditional angled stitched. The compression strength and compression modulus of integrated stitched sandwich structure composites increase with the increase of the number of stitching yarn. However the specific compression strength will decrease when the number of stitching yarn is high. The rationality of the established finite element model is validated by comparing with numerical calculation results and test results. It indicates that the model could be used to predict the compression modulus.