ON THE AXIAL AND INTERFACIAL SHEAR STRESSES DUE TO THERMAL MISMATCH IN HYBRID COMPOSITE SHEETS

A simple analytical model has been developed which allows the determin ation of the axial and the interfacial shear stresses which can occur in hybrid fiber composites as a consequence of the mismatch in coeffic ients of thermal expansion and Young's modulus. The configuration cons idered is a finite-width hybrid composite monolayer with alternating h igh- and low-modulus fibers. To account properly for the interfacial s hear between fiber and matrix, a modified shear-lag model is used whic h permits extensional deformation due to thermal expansion of the matr ix in the fiber direction. Typical stresses due solely to temperature changes are calculated, and these show steep boundary-layer edge stres ses at free corners.