Transverse elastic moduli of unidirectional fiber composites.

A mathematical model is developed to predict the transverse elastic moduli of unidirectional fiber composites. Two cases are investigated for fiber/matrix interfacial bondings: perfect bonding and complete debonding. The elastic property of a fiber is assumed to be transversely isotropic. Elastic interaction among fibers is considered there. In the case of complete debonding, the cavity formation model is adopted and the fiber and the cavity around it are replaced by an anisotropic imaginary inclusion. Effective elastic moduli are obtained for the transverse tensile and compressive modes, and for the transverse and longitudinal shear ones. The limiting case in which the matrix contains fiber-shaped voids in place of fibers is also touched upon. Numerical case studies are presented for two metal matrix composites, where the effect of interfacial bonding state on the transverse properties is mainly discussed.