Ultrasonic moulding: Current state of the technology

Ultrasonic moulding, also known as ultrasonic microinjection moulding, is a new technology that uses high-power ultrasound to melt and mould thermoplastic polymers to produce samples with mini- and micro-features. The main feature of this technology is the use of ultrasonic energy as the heating source instead of a conventional injection screw. Since 2002, several authors have experimentally and theoretically studied the ability of ultrasonic energy to mould polymers. However, different machine configurations and experimental design strategies have been used, which makes it very difficult to compare the results obtained from different articles. In this report, the authors have compiled experimental studies on the ultrasonic moulding process and analysed them along with providing a theoretical framework. An accurate description of the process and the machine configurations used in the literature is also presented. The results obtained from the analysis are summarized and discussed, and possible next steps to further the research in this field are suggested.