Rheological Behaviour of Metal Powder Suspensions Under Dynamic Loading

The dynamic rheological properties of injection moulding of feedstock powder-binder blends (suspension) based on iron powder and HDPE (High Density Polyethylene)were investigated by using a parallel plate rheometer. The solid content ranging from 30 to 60 vol% of the total volume of loaded metal powder, compatibilizer, stearic acid, and stearamide. The dynamic rheological response of the materials was used to analysis the effect of the mentioned factors on the material functions of the mixtures (dynamic viscosity η*, storage modulus G’, and loss modulus G”) at frequency range 0.1- 100 s-1. These parameters showed large differences in the response of the suspensions with changes in loading and addition of compatibilizer. All dynamic parameters increase by increasing the volume fraction of solid loading. As compatibilizer, stearamide shows asignificant effect on rheological behaviour of suspensions. Falkner-Schmit models wereused to fit the experimental rheological data. It was found that our experimental data andmodified composition fit the modified forms of these models.