Fiber/Matrix Interface in Composite Materials

Interfaces are among the most important yet least understood components of a composite material. In particular, there is a lack of understanding of processes occurring at the atomic level of interfaces, and how those processes influence the global material behavior. There is a close relationship between the processes that occur on the atomic, microscopic, and macroscopic levels.

In fact, knowledge of the sequences of events occurring on these different levels is extremely important in understanding the nature of interfacial phenomena. Interfaces in composites, often considered as surfaces, are in fact zones of compositional, structural, and property gradients, typically varying in width from a single atom layer to micrometers.

Characterization of the mechanical properties of interfacial zones is necessary for understanding mechanical behavior. The mechanical characteristics of a fiber/resin composite depend primarily on the mechanical properties of the combined material, the surface of the fiber, and the nature of the fiber/resin bonding as well as the mode of stress transfer at the interface.