Thermoforming with Integrated Design Elements

• Applicant: Professor Dr.-Ing. Christian Bonten
• Subject Area: Plastics Engineering
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 436232907

During the thermoforming process thermoplastic sheets are formed into three-dimensional parts. The forming process is usually carried out using a one-sided tool by applying pressure differences (vacuum and/or compressed air) and/or by means of stretching aids. Thermoforming is usually used to produce packaging articles but also for producing technical components. Therefore, the thermoforming process stays in competition with injection molding. However, thermoforming still has some disadvantages compared to injection molding. In comparison to injection molding, the freedom of design in the thermoforming process is limited. With the thermoforming process only shell-shaped parts without functional elements (e.g. ribs, screw bosses, snap-fits) can be produced. Functional elements can only be attached by a further processing step, such as welding or gluing. Nevertheless, a new research project, thermoforming with integrated design elements, makes it possible to integrate functional elements into the thermoforming process. Through this process integration, the subsequent step of joining design elements can be saved. During thermoforming with integrated design elements, first an insert must be placed in the mold. Afterwards the sheet can be formed and at the same time welded to the insert. This creates a cohesive connection between the insert and the thermoplastic sheet.Within this research project, the basic material relationships for the thermoforming process with integrated design elements have to be investigated. This will help to understand this new process. Based on these findings, a process modeling will also be developed. The aim of this research pro-ject is to investigate the individual process parameters and influences on the quality of the welded seam during thermoforming with integrated design elements. In addition, the results have to be used to check and enhance existing models for describing the acting mechanisms of welding processes.

• DFG Programme: Research Grants