MICROSTRUCTURE FUNCTIONS FOR A MODEL OF STATISTICALLY INHOMOGENEOUS RANDOM-MEDIA

We propose a model for statistically inhomogeneous two-phase random me dia, including functionally graded materials, consisting of inhomogene ous fully penetrable (Poisson distributed) spheres. This model can be constructed for any specified variation of volume fraction and permits one to represent and evaluate certain n-point correlation functions t hat statistically characterize the microstructure for this model. Unli ke the case of media, the microstructure functions depend upon the abs olute positions of their arguments. However, as with homogeneous rando m media, this microstructural information will be useful in obtaining rigorous estimates of the effective properties of such systems.