The amount of interpenetration of the two-particle system was studied analytically and experimentally. Using the models of neck growth in various sintering mechanisms, the geometrical relationship between the neck radius and the amount of interpenetration was derived. In the consideration of the atomic flow the following three shrinkage mechanisms were assumed: variable-radius-interpenetration mechanism, constantradius-interpenetration mechanism and deformation-interpenetration mechanism. The amount of interpenetration became larger in the above order in the same neck radius.
In the experiment, the amount of interpenetration in sintering was measured in two particles system using SEM. After the corrections, the amount of shrinkage in the experiment was distributed between the variable-radius-interpenetration and constant-radius-interpenetration in the calculated result.