Effects of quasi-3D stacking architecture on interlaminar shear strength and void content of FRP

To improve the interlaminar shear strength (ILSS) of composite laminate, three different quasi-3D stacking architecture (q-3DSA) laminates were fabricated by using automated fiber placement process and a traditional 2D stacking architecture (2DSA) laminate was fabricated as the control sample. The distribution of voids, the density, and the ILSS of four types of laminates were tested. The results indicated that the void content of the different q-3DSA laminates was approximately 0.71%-3.07% greater than that of the 2DSA laminate, but the ILSS of q-3DSA laminates was 5.49%-12.54% better than that of the 2DSA laminate. The microstructure images showed that the cracks spread along the interface between the adjacent layers in the 2DSA laminate, while the cracks cross two or more layers in the q-3DSA laminates. This behavior indicated that the q-3DSA improved the ILSS by dispersing the interlaminar load through the bended and interlaced tows in the laminate.