Load transfer from fiber to polymer matrix, studied by measuring the apparent elastic modulus of carbon fiber embedded in epoxy

Load transfer from a single carbon fiber to the surrounding epoxy matrix was studied by measuring the apparent tensile modulus of the fiber while the fiber was embedded in epoxy and comparing the apparent modulus (1650 GPa) with the real modulus (230 GPa). Thus, it was found that 87% of the tensile load applied to the fiber was transferred to the epoxy.