Thermoelastic homogenization of periodic composites using an eigenstrain-based micromechanical model

摘要

This paper presents a study on effective thermoelastic properties of composite materials with periodic microstructures. The overall elastic moduli and coefficients of thermal expansion of such materials are evaluated by a micromechanical model based on the Eshelby equivalent inclusion approach. The model employs Fourier series in the representation of the periodic strain and displacement fields involved in the homogenization procedures and uses the Levin's formula for determining the effective coefficients of thermal expansion. Two main objectives can be highlighted in the work. The first of them is the implementation and application of an efficient strategy for computation of the average eigenstrain vector which represents a crucial task required by the thermoelastic homogenization model. The second objective consists in a detailed investigation on the behavior of the model, considering the convergence of results and efficiency of the strategy used to obtain the approximate solution of the elastic homogenization problem. Analyses on the complexity of the eigenstrain fields in function of the inclusion volume fractions and contrasts between the elastic moduli of the constituent phases are also included in the investigation. Comparisons with results provided by other micromechanical methods and experimental data demonstrate the very good performance of the presented model.