On numerical simulations of powder injection molding

The effect of particle migration on powder injection molding (PIM) is numerically studied. Shear induced particle migration is represented by the model of Phillips for the dynamics of the particle concentration under the influence of shear rates and spatially varying viscosities. The viscosity of the suspension of particulate metallic or ceramic material and polymeric binder depends on the local shear rate in the polymeric binder, the particle concentration and the temperature. A numerical algorithm is developed to solve the resulting strongly coupled Non Newtonian thermal free surface flow modell in arbitrary three dimensional domains. The software is validated by comparison with published experimental results on pressure driven pipe flow. As industrial application we simulate the powder injection molding of a complex three dimensional part for realistic process parameters and compare with experiments.