Modeling of energy absorption of short fiber composite considering interfacial properties of fiber/matrix

A generalized mathematical model of energy absorption of randomly oriented short fiber composite is developed on the basis of result of single-fiber pull-out test and some assumptions obtained from experimental investigation of the fracture of the composite of Aramid short fiber. Concept of the pull-out test is incorporated to the model, such that the fibers intersecting a fracture plane (where the fracture of composite occurs) would pull out or fracture like single-fiber pull-out test. The energy contribution of each fiber in the fracture plane is calculated for different embedded length and orientation to estimate the total fracture energy. According to the model, it is found that energy absorption depends upon the intrinsic properties of the fiber and matrix, volume fraction, critical embedded length of the fiber, fiber length and orientation of the fibers in the matrix. Analytical results obtained by the model are compared with the experimental results of Aramid short fiber composite.