ABSTRACT
Micromechanics are a study of mechanical properties of unidirectional composites in terms of those of constituent materials. In particular, the properties to be discussed are elastic moduli, hygrothermal expansion coefficients and strengths. In discussing composite properties it is important to define a volume element which is small enough to show the microscopic structural details, yet large enough to represent the overall behavior of the composite. The properties of a composite depend on the geometrical arrangement and the properties of its constituents. The exact analysis of such structure-property relationship is rather complex because of many variables involved. The composite stress and strain are defined as the volume averages of the stress and strain fields, respectively, within the representative volume element. By finding relations between the composite stresses and the composite strains in terms of the constituent properties, we can derive expressions for the composite moduli.
