Effect of apertures on tensile property of warp-reinforced 2.5D woven composites notched plates

Abstract

As a typical structural material, the mechanical properties of the notched plate have received extensive attention. In order to explore the tensile properties of warp-reinforced 2.5D woven composite notched plate, three apertures of specimens were manufactured. Tensile experiments were carried out, and full-field strain distribution were obtained by digital image correlation (DIC) technique. A multi-scale progressive damage method was developed to predict the strength and to analyze failure mechanism. Subsequently a representative unit-cell model considering the surface extrusion and homogenization models of the notched plates were proposed, and the damage propagation was analyzed. In addition, the internal damage and failure fracture were examined with the help of micro computed tomography (Micro-CT). Based on the experiments and numerical models, tensile behaviors and failure mechanism were discussed. The results show that the errors of tensile modulus and strength between the experimental and simulation value were less than 6%. Moreover, with the increase of aperture, the tensile strength of the notched plate decreased almost linearly, but the stiffness did not show a significant relationship with the aperture. The failure modes contained the warp yarn breakage and matrix crack, and the damage were mainly located on left/right side of the holes.