Research On Interfacial Debonding Of Single-Fiber Pullout Of Composite

Composite materials have been widely used in various fields of national economy, which has been received more and more attention and importance. It is well recognized that the interface between fiber and matrix plays an important role in the mechanical properties of fiber-reinforced composite. Therefore, it is very important to study the failure mechanism of the interface of composite material in the practical engineering.In the present work, based on the analysis of stress field of the new theoretical model of the single-fiber pullout problem in Chapter 2, we analyze the interfacial debonding by the interfacial shear strength and potential energy release rate. The work of this paper mainly includes the several parts as follows: the advantages and application of composite materials and its related research background are outlined in Chapter 1, the new theoretical model of the single-fiber pullout problem and the analysis of stress distribution in a fully bonded and debonded region are introduced in Chapter 2. In Chapter 3, studied is the interface debonding criterion by the interfacial shear strength. With a hypothetical glass fiber/epoxy composite as a model example, calculated results of the applied stress/displacement curves of the fiber pull-out tests are given for different radial thermal residual stress, model lengths, fiber pull-out rate and fiber volume contents. In Chapter 4, we investigate the interface debonding criterion by the potential energy release rate. The influence of the radial thermal residual stress, model lengths, fiber pull-out rate and fiber volume contents on the fiber pull-out process is studied. Using the same material parameters, the results of the two theories are in agreement. Finally, this work is concluded, and future works on the topic are proposed.