Numerical modeling for powder-binder compound flow in metal injection molding

To investigate the complex physical flow behavior of the powder-binder compound, and to optimize the process condition in the metal injection molding process, two numerical modelings have been developed. The first model is the granular model with composite element to evaluate the microscopic rheology of mixed compound. The smoothed particle modeling is applied in the mesoscopic level, to link both the micro- and the macroscopic physics of mixed compound. Here, both powder elements and binder flows are directly traced with consideration of cooling effect by thermo-mechanical coupling method. These numerical models especially focus on the prediction of the inner state of the mixed compound and the effects of powder characteristics to flowability and formability. Several numeral examples are demonstrated and compared with the short shot patterns of the actual tool molded products.