On the Possibility of Approximation of Irregular Porous Microstructure by Isolated Spheroidal Pores

Calculation of the effective elastic constants of a material with irregularly shaped porous space is discussed. It is shown that isolated pores of irregular shapes may be approximated, with good accuracy, by the spheroidal ones. Procedure of evaluation of the average aspect ratio from the photomicrograph is described. Several commonly used approximate schemes are applied to predict effective Young’s and shear moduli of a material with spheroidal pores. Comparisons of these predictions with the experimentally measured elastic constants for completely sintered hydroxyapatite exhibit reasonably good accuracy. The best agreement is given by self-consistent and effective field methods.