Fatigue behaviour of non-crimp 3D orthogonal weave and multi-layer plain weave E-glass reinforced composites

The paper studies tension–tension fatigue behavior of a single-ply non-crimp 3D orthogonal weave Eglass composite and of a laminated composite reinforced with four plies of a standard plain weave fabric. Both composites have same total thickness and very close fiber volume fraction. The paper presents the description of the materials, the results of quasi-static tensile and of tension–tension fatigue tests, including the damage development during fatigue tensile loading. The non-crimp 3D woven fabric composite, loaded in both principal in-plane directions (warp and fill), shows the best quasi-static tensile properties and, when loaded in the fill direction, exhibits much longer fatigue life than its laminated plain weave counterpart. During both quasi-static and fatigue loading, the latest damage initiation is observed for the 3D woven composite in both in-plane directions. The PW laminate develops delamination between the plies for each maximum stress in the cycle considered. Contrary to that, the 3D composite is not affected by delamination neither under quasi-static nor under fatigue loading conditions.