Prediction of charging rate in ultrasonic vibration of injection molding

As a demand for polymer products rises lately, manufacturers pay attention to advance in productivity of polymer products. In case of thin and light-weighted products demanded in current market, there is a limit of productivity due to the characteristics of polymer. Since manufacturers in ultrasonic process depend on their experience and intuition to solve the problem, it causes inefficient productivity and insufficient filling of cavity. In this study, based on the assumption that polymer melts are non-Newtonian, the effects of ultrasonic vibration in filling process are analyzed numerically to predict more effective ultrasonic process. The results show that polymer behaviour in ultrasonic vibration can be estimated and more efficient modal conditions are proposed. Subsequently, it is demonstrated that the low viscosity of polymer melts due to ultrasonic vibration causes an improvement in filling rate.