The influence of matrix plasticity on the failure strain of transversely loaded composite materials

The influence of the matrix on the transverse tensile properties of unidirectional carbon fiber-reinforced composites is investigated, based on epoxy matrixes with various failure strains. Finite element micromech. analyses are used to compare the deformation of the matrix in fiber-reinforced plastics with the deformation in rubber-toughened plastics. The stress situation leads to a brittle behavior in the former and favors a high failure strain in the latter with ductile matrixes. It is expected that the combination of rubber coated fibers with a ductile matrix yields composites with high transverse failure strains