Properties of stitched composite laminates-fatigue performance of composite laminates with an open-hole

Experimental study was carried out on the fatigue performance of stitched composite laminates with an open-hole, in which the effect of stitching and its direction on the tensile fatigue damage propagation rule of the composite laminates with a hole was studied. The stress distribution of non-stitched and stitched laminates with a hole was calculated through finite element method (FEM). Based on this, the mechanism of tensile fatigue damage origination and propagation of stitched laminates with a hole was analyzed. The results show that the mechanism for the tensile fatigue damage origination and propagation of laminates with a hole has been changed by stitching. Stitching direction has an obvious effect on tensile fatigue damage propagation. The interlaminar shear stress plays an important role in damage origination and propagation for 45° stitched laminates with a hole. It is likely that certain other main damage areas will arise with 45° stitched laminates with a hole in addition to the damage at the hole edge.