Influence of inclusion shape on viscous sintering

The effect of inclusion shape on sintering is studied from micromechanical considerations. The matrix is assumed linearly viscous, and the inclusions are rigid and are dispersed at random. First, an exact link between the overall shrinkage rate and the effective bulk viscosity is established, followed by the derivation of upper and lower bounds for both the overall shrinkage rate and the average stress in the matrix. Then the overall shrinkage rate and the average stress are estimated for axi-symmetric ellipsoidal inclusions by a mean-field method. The influence of the aspect ratio of the inclusions is discussed in details.