Umformtechnologie für komplexe Leichtbaustrukturen mit polymeren Schäumen in Verbundbauweise

Responsible: Oehl, G.

The aim of the project is to develop a process that enables the manufacture of a three-dimensional component made of a foam sandwich composite that meets the fire protection requirements of the aviation industry. The flame protection is generated by the selection of suitable and, at best, industry-specific certified starting materials. Material selection and development directly interact with process development, as different starting materials require different processing methods. For complex structural elements, an appropriate forming strategy must be developed. The cured sandwich can no longer be formed when using thermoset face sheets, so that the forming must be carried out beforehand. The aim is therefore to develop a process route in which the thermoplastic foam and the textile are formed together and impregnated with the still liquid resin system. In order to save tooling and process costs, a single-stage process is being developed in this project, in which the sandwich composites can be produced without the use of a hot press or an autoclave, using only a vacuum. By forming the cover layers together with the foam core and impregnating them in the same tool, it should be possible to produce complex components with near-net-shape geometry in a short time. Material selection and development support the optimization of the process through preliminary tests on a laboratory scale. It will be examined to what extent foam and resin are compatible and how, for example, the exothermic curing reaction of the resin can thermally support the forming process. In addition, it should be possible to integrate metallic force introduction elements into the component without having to carry out further post-processing steps. For this purpose different techniques have to be tested, but all of them aim at an insert integration directly in the forming process. For this purpose, the forming tool is provided with suitable recesses or pins in order to position the inserts securely.