Micromechanical formulation of multilayered composites in thermoelasticity

Abstract

This paper presents the development of an analytical formulation to compute the stress and thermal fields in composite laminates as a result of through-the-thickness temperature gradient. The analysis couples a macro-mechanical formulation with a micro-mechanical one. The macro-mechanical formulation is based on thick laminated plate theory that enables us, among other things, to calculate the stresses and thermal gradient on the boundaries of each individual lamina. The obtained values on the boundaries of a lamina will constitute boundary conditions for a micro-mechanical problem, which is solved using the methodology of 'Heterogenization' that enables us - under the assumption that the fiber is far enough from the inter-laminar interfaces, so that the fiber can be treated as being in a matrix of infinite extent - to calculate analytically the stress and thermal fields in the lamina. The final state of stress is obtained within the matrix, inside the fiber, and at the fiber/matrix interface. The coupling of these two formulations is necessary to capture the local state of stress, which can be used to predict failure in composite lamina. An example is presented to illustrate the method. © 2001 by the American Institute of Aeronautics and Astonautics, Inc. All right reserved.