Chapter 9 - Modeling of Fiber–Matrix Interface in Composite Materials

Abstract

Publisher Summary The properties of the fiber–matrix interface are of great importance for the macroscopic mechanical properties of composite materials. The two-dimensional interphases or finite-thickness interphases are considered when analyzing the interaction between fibers and matrix in composites. On the molecular level, an interphase can be envisaged, with a chemical or physical bond to the residual groups on the fiber surface, and an effective functional gradient in the radial direction with properties different from those of the bulk matrix—for example, by interdiffusion of polymer networks of the size and the matrix. A simple relationship between the fiber strength and the interface strength is described in the chapter. This relationship makes it possible to establish that the strength properties of the interface should be to obtain an overall composite failure instead of a fiber–matrix interface failure. A mathematical expression is described in the chapter that relates the interlaminar shear stress, interfacial shear stress, fracture toughness, and physical and mechanical properties of the composites.