Ultrasonic plastification speed of polymer and its influencing factors

Abstract

The melt filling difficulty in micro cavity is one of the main challenges for micro-injection molding (MIM). An approach employing ultrasound in MIM was proposed. The approach was extensively studied through experiments with a home-made experimental ultrasonic plastification device. The results of the experiments show that polymer ultrasonic plastification speed increases with ultrasonic supply voltage and plastification pressure. When the ultrasonic supply voltage is 200 V and the plastification pressure is 2.0 MPa, the polymer ultrasonic plastification speed reaches the maximum value of 0.111 1 g/s. The results also indicate that the ultrasonic cavitation effect is the most significant effect of all the three effects during polymer ultrasonic plastification process.

Keywords

ultrasonic plastification / plastification speed / ultrasonic cavitation / micro-injection molding

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