Time dependency of carbon/epoxy interface strength

This paper describes time-dependent fiber/matrix interfacial strength of carbon fiber reinforced polymeric composite. The time-dependent interfacial strength is extracted from the results of transverse tensile tests with various loading rates and their fractography in the unidirectional composite. The results show that the material failure is dominated by interface failure under relatively high-loading rate whereas matrix failure is dominant under relatively low-loading rate. In light of the results, it is concluded that the time dependency of the interfacial strength might be neglected or at least could be less significant than that of matrix strength.