Determination of overlapping degree of interfacial layers around polydisperse ellipsoidal particles in particulate composites

The determination of overlapping degree of interfacial layers is crucial to evaluate physical properties of particulate composites. The purpose of the present work is to develop a theoretical scheme for the overlapping degree of interfacial layers around polydisperse ellipsoidal particles in particulate composites. Comparing with numerical results of the actual interfacial volume fraction and theoretical results of the interfacial overlapping degree around spherical particles in the literature, the accuracy of the developed theoretical scheme is tested. Based on the present scheme, the dependence of the interfacial overlapping degree on geometrical configurations of particles is investigated quantitatively through sensitivity analysis. It is found that the effects of those factors on the interfacial overlapping degree have similar behaviours to that on the actual interfacial volume fraction. For instance, the interfacial overlapping degree increases with the increase of the interfacial layer thickness and the volume fraction particles, but it decreases with the increase of the maximum equivalent diameter of ellipsoidal particles. Interestingly, we find that the interfacial overlapping degree strongly depends on the shape of particles; that is, the interfacial overlapping degree increases as particles deviate from perfect spheres. These results can further be used as theoretical criteria for guiding practical works.