Analytical procedures are developed for a composite system consisting of shape memory alloy fibers within an elastic matrix subject to uniform temperature. Micromechanics for the calculation of the equivalent properties of the composite are presented by extending the multi-cell model to incorporate shape memory alloy fibers. A three phase concentric cylinder model is developed fro the analysis of local stresses which includes the fiber, the matrix, and the surrounding homogenized composite. The solution addresses the complexities induced by the nonlinear dependence of the in-situ martensite fraction of the fibers to the local stresses and temperature and the local stresses developed from interactions between the fibers and matrix, during the martensite and reverse phase transformations. Results are presented for a Nitinol/Epoxy composite. The applications illustrate the response of the composite in isothermal longitudinal loading and unloaidng and in temperature induced actuation. The local stresses developed in the composite under various stages of the martensite and reverse transformation are also shown.
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