Thermo Flow Forming (TFF)

High performance polymers generally exhibit very high melt viscosities as result of their high molecular weight. They are therefore very difficult to process and require heavy-duty processing equipment. In some cases they cannot be processed at all using conventional melt processing techniques. In spite of this processing restriction, there is high demand for microparts from high performance polymers due to their excellent properties. In this study, a novel processing method called Thermo Flow Forming (TFF) has been developed for manufacturing parts made from high performance polymers. The TFF process is based on the flow of polymer material in its thermoelastic state, between its glass transition and melting temperatures, by compressive flow thermoforming. The TFF process has been successfully tested using high performance polymers such as polyphenylene sulfide (PPS), polyetheretherketone (PEEK) and unmouldable polytetrafluorethylene (PTFE). Thus, the TFF is a realistic alternative technique to the existing micromoulding processes. It can replace the wasteful and inefficient conventional machining of microparts made from unmouldable high performance polymers such as PTFE.