Simulation of microscopic shrinkage behaviour in sintering of powder compact

A method for simulating microscopic shrinkage behaviour of powder particles in sintering of a compact is proposed on the basis of the granular element method. In this method, the powder particles are modelled as many circular elements undergoing viscoplastic deformation due to surface tension during the sintering, and the microscopic shrinkage is calculated by equilibrating forces acting on the elements. The variation in shape of necks between the elements during the sintering is taken into consideration. Plane-strain shrinkage in sintering is calculated under regular and irregular dispositions of powder particles. In the regular disposition of powders having the same diameter, the obtained shrinkage behaviour is compared with the experimental one using glass rods and the calculated one by the viscoplastic finite-element simulation respectively. It is shown from the simulation of irregular disposition that the densification due to the sintering is accelerated by mixing powders having different diameters.