Application of the v-notch shear test for unidirectional hybrid composites

The v-notch (losipescu) shear test was investigated as a mean for determining the in-plane shear modulus and strength of unidirectional hybrid composites. Two types of hybrid systems having different fiber tow volume fractions composed of carbon and glass fiber tows with epoxy matrix were used for this study. A fiber tow-based finite element analysis was also used to simulate the v-notch shear test for characterizing stress-strain distributions of the specimen. Our experimental and numerical evaluation shows that although the local inhomogeneity inherent in the hybrid composites affects the composite mechanics at a small scale in the v-notch specimen, the test still exhibits a limited region possessing a reasonably pure and uniform stress-strain state between the notches to meet the requirement for a desired shear test. Thus, the study indicates that the v-notch test can be used for the shear testing of the hybrid composites studied when it is correctly used.