Experimental investigation on impact response of sandwich composites integrated with a novel 3D multi-layer stitched core.

Impact damage resistance of the sandwich composites affects the structure reliability and crucially depends on the core. The weak junction of core unit-cell walls causes a catastrophic failure on sandwich composites under impact load. Stitching is an efficient and easy way to obtain the strengthened core unit-cells. In this study, the impact behavior of glass/epoxy face sandwich composites integrated with a novel 3D multi-layer stitched core were investigated. The peak forces and absorbed energy of sandwich composites were increased as the number of core layer increased. The increase in core layers and core dimensions caused more flexible sandwich composites. The core was more effective in the energy absorption mechanism of the sandwich composites than faces with the increased stitching density and decreased unit-cell size of core. The number of core layers, dimensions of core unit-cells and stitching density were found to be most important parameters for the impact failure of sandwich composites. [ABSTRACT FROM AUTHOR]