A refined method for estimating fiber and interfacial shear strength by using a single-fiber composite

Abstract
In estimating interfacial shear strength from the fragmentation process of fibers in single-fiber composites, a problem arises as to the value of the fiber strength if the fiber strengths distribute widely and strongly depend on the fiber length. To overcome this problem, a refined analysis method for simultaneously estimating the fiber and the interfacial shear strength from the fragmentation process has been shown. Agreements between the values estimated with the proposed method and the results of the single-fiber tensile and the direct shear tests have been obtained. It has been shown that the estimation of the interfacial shear strength using the proposed method is insensitive to the matrix properties if the interfacial shear strength is unaltered by the matrix properties, and that the variations of the distribution parameters of the fiber strength is significantly smaller for the proposed method as compared with the single-fiber tensile tests. The results obtained by applying the proposed method to various carbon fibers have been shown.