Effect of Core Stitching on Flexural Properties of Lightweight Sandwich Composites

This chapter presents the flexural behavior of low-density stitched polymer foam core sandwich composites. The stitching was made into PVC foam core materials to reinforce the core through the thickness direction. Once the PVC foam core materials were predrilled, E-glass fiber yarns with 600 tex were used to stitch the sandwich cores. The stitching effect was investigated on the sandwich structures with carbon fiber and glass fiber face sheets. The sandwich composites were manufactured with the vacuum bagging method, and the whole face sheets and the sandwich were co-cured. The sandwich panels were cut to obtain flexural test specimens according to ASTM C393 standard. The flexural tests were carried out with three-point bending loading. The effect of core stitching on the flexural characteristics of sandwich composites was revealed. A significant increase in bending load capacity and sandwich rigidity was obtained.