Increasing the interlayer fracture toughness of polymer fabric composites using local 3d-reinforcement (felting)

Introduction. One of the reasons for undesirable delamination of polymer composites with fabric reinforcement is low transverse shear properties. It is known that the reinforcement of polymer fabric composites in the Z direction reduces the sensitivity to delamination and increases the viscosity of interlayer fracture. Various methods of three-dimensional reinforcement of polymer fabric composites are proposed in the literature. However, they complicate the manufacturing process of the structure. The problem is solved by the method of three-dimensional reinforcement proposed in this article - felting. This is a local reinforcement of the composite in the Z direction with minimal production changes. The degree of Z-reinforcement is determined by the felting density, i.e., the number of needle punches per 1 cm2 of the fabric package. The work is aimed at evaluating the effect of felting on the interlayer crack resistance of a composite material.