Elastic and thermal expansion behavior of two-phase composites

A first attempt has been made to propose a model to predict both the elastic constants and thermal expansion coefficient of two-phase composites. The model assumes that the two-phase composite is composed of many identical unit cells, and each unit cell is composed of a continuous matrix phase and an elongated particulate. The unit cell is further divided into several subunits; the two phases in each subunit are arranged either in series or in parallel. By inputting the basic information of each phase, the model could predict the upper and lower bounds of various elastic constants (e.g. elastic, shear and bulk moduli and Poisson's ratio) and thermal expansion coefficient of two-phase composites. Comparisons between the model predictions and available experimental measurements are carried out. There is an excellent match between the stimulated upper and lower bounds and experimental data over the entire composition range.