Experimental and numerical investigation on damage mechanism in asymmetric tapered laminates under tensile loading

It is one of the most advanced technologies to use automated fiber placement (AFP) to manufacture aero-engine composite blades. The layup sequence of composite blades has strong designability due to the variation of section thickness. In this article, tapered laminates are manufactured by AFP. The influence of different resin pockets and laying methods on the properties of tapered laminates are analyzed by tensile test, finite element modeling and macroscope images. The specimens are analyzed by failure mode, strength and crack propagation and suggestions for improvement are put forward. The results show that the resin pocket height and taper ratio have a great influence on the tensile strength. The 1:30 taper ratio has a higher strength than the 1:20 taper ratio, at least 54.22% higher. In addition, the crack near the thin end of the resin pocket is tend to cause cracks, and the delamination is also tend to reach this position. Experimental measurements and FEM results correlate very well.