摘要：

Simple models, based on strength of materials approach, have been developed to understand the deformation behavior of two-phase composites. The models have been derived by considering a unit cell, representing an idealized composite-microstructure consisting of cubic inclusions distributed uniformly in a continuous matrix. Using experimental as well as finite-element data, simple relationships are shown to adequately describe the elastic, plastic and steady-state creep deformation characteristics. In particular, the predicted trends in composite elastic moduli are much closer to experimental data than the Hashin-Shtrikman bounds, for composites with constituents having large differences in elastic moduli. Plastic deformation as well as steady-state creep deformation behavior were deduced by dividing the unit cell into elements of matrix and reinforcement and accounting for the constrained deformation of matrix between rigid inclusions. It is shown that the increase in flow stress due to reinforcement as well as the stress-strain curves can be calculated from the simple equations resulting from this model. Results of studies to examine the effects of complex microstructural arrangements in two-phase materials on deformation and creep behavior are also presented. The promise of the present unit cell based method of calculation for the prediction of properties of multiphase materials is illustrated.

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