Role of Interphase on the Elastic Behavior of Composite Materials: Theoretical and Experimental Analysis

The study and design of composite structures raises numerous difficulties due to the high level of heterogeneity and to the small size of the fillers. One of the most usual solutions consists in replacing the composite material by a homogeneous medium which is considered as "macroscopically" equivalent. This kind of approach, named homogeneization, aims to provide every mechanical characteristic of the composite according to the mechanical and geometrical features of its constituents. The aim of the present paper is twofold: (1) to review the most usual homogeneization approaches for linear elastic behavior in order to obtain their own range of validity in comparison with experimental data, and (2) to determine experimentally and numerically the effect of a third phase, named interphase, on the linear elastic behavior of fiber composites.