Comparison of rheological analytic model with numerical simulation in powder injection molding filling process

Abstract

Mathematical model of filling disk-shaped mold cavity in steady state was studied. And the mathematical model under vibration field was developed from the model in steady state. According to the model of filling disk-shaped mold cavity in steady state, the filling time, the distribution of velocity field and the pressure field were obtained. The analysis results from rheological analytic model were compared with the numerical simulation results using Moldflow software in the powder injection molding filling process. Through the comparison, it is found that it is unreasonable to neglect the influence of temperature when calculated the pressure changing with the time at the cavity gate, while it can be neglected in other situations such as calculating the distribution of the velocity fields. This provides a theoretical reference for the establishment of correct model both in steady state and under vibration force field in the future.

Keywords

mathematical model / Moldflow software / vibration force field / powder injection molding / filling process

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