Abstract
Glass/epoxy interfacial tensile strength is investigated by the cruciform specimen method. The conventional transverse tensile test for single fiber composite is one of methods for evaluating the interfacial tensile strength, but stress singularity at the specimen edge is a very complicated problem to be solved. A cruciform specimen which has large width only around fiber embedded in transverse direction can potentially prevent the stress singularity problem. The cruciform specimen geometry is first discussed by means of finite element analysis considering experimental conditions. Transverse tensile test is conducted and an interfacial debonding which initiates at the middle of specimen not at edge is observed using the cruciform specimens. The interfacial tensile strength can be obtained by the value of stress concentration factor at interface multiplied by specimen stress. The location which the debonding initiates from is discussed and the validity of the evaluation method in this study is verified when interfacial tensile strength is as high as or lower than interfacial shear strength.
