Polymer forming machine for thermoplastic pellets

• Subject Area: Production Technology
• Term: Funded in 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 445455137

The production of components and assemblies for medical devices and implants made of plastic by injection moulding is widespread. Also the production by means of different Rapid-Prototyping procedures (RP, also called 3D printing or additive manufacturing) belongs to the state of the art. Especially in medical technology, however, certified or approved materials are required that can be used independently of the selected RP process. The device applied for is capable of simultaneously processing up to any three thermoplastics in granulate form. Thus, genuine materials approved for medical products by their respective manufacturer can be used. The aim is to use the device to answer medical technology questions (e.g. implants for automated wound closure, radiotranslucent drives, multi-axis force sensors for haptic user interaction, etc.). The device should make it possible to manufacture these systems in a single operation and to conduct the experimental investigation without much reworking. The device is used for the additive production of thermoplastic parts in granulate form. This ensures that any non-pre-treated thermoplastics (forming into filament form, coating, powder) can be used. Thus, also plastics with special properties (elastic, electrically conductive, absorbable, translucent, magnetic etc.) can be deployed, which cannot be used with other systems. In addition, a device is required, which dispenses the material not in the form of a filament or thread but as droplets in order to achieve the most isotropic properties of the component possible. Last but not least, a system is required that can process three different materials simultaneously in order to process both supporting and geometric structures and special materials (see above). It should be possible to manufacture components with dimensions of up to approx. 120×120×200 mm³. An excessively large workspace is not useful, since the temperature gradient in the workspace can lead to deformation of the components.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Kunststoff Freiformgerät für Thermoplaste in Granulatform
• Instrumentation Group: 2110 Formen-, Modellherstellung und gießereitechnische Maschinen
• Applicant Institution: Universität Stuttgart
• Leader: Professor Dr. Peter Pott