Development of a continuous process for the intrinsic production of polymer-metal composite structures

• Applicants: Professor Dr.-Ing. Markus Stommel; Professor Dr.-Ing. A. Erman Tekkaya
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 490989965

Composite components made of metal and polymer are increasingly being used in order to combine the properties of different materials and thus make the best possible use of the potential of available resources. Such hybrid components are usually produced in several successive manufacturing steps, first by manufacturing the metal component and then by adding the polymer component. In contrast to this, there are few direct processes that allow metal and plastic to be shaped together. The existing direct processes, such as Polymer Injection Forming, are limited to sheet metal forming. Extrusion is an important manufacturing process for the production of long profiled semi-finished products, which are used in various sectors, such as the automotive sector, construction, transport or electronic components. Hybrid profiles, such as window profiles or insulated piping, have so far been produced by assembling extruded light metal profiles and extruded polymer profiles. Due to the sequential process sequence, the product range is limited, since subsequent assembly of the components must always be taken into account. The production of solid components from aluminium-plastic composite profiles using an intrinsic direct process, i.e. the combination of light metal extrusion and plastic extrusion, has not been investigated so far.The aim of the research project is therefore the fundamental investigation of intrinsic hybrid extrusion. This is intended to expand the existing range of components and to combine the advantages of the different manufacturing processes. In order to achieve this, the technological requirements must first be created in order to harmonise the individual processes of light metal forming and plastic moulding. For this purpose, the relevant process variables and process windows in intrinsic extrusion with continuous profiles are investigated on simple geometries. Due to the process-related exclusion of oxygen in the joining zone and the high pressures, improved composite properties are expected which improve the performance of intrinsically produced components compared to sequentially produced components. A further essential advantage of the direct process is the new possibilities in component design. By controlling the process parameters, profiles graded over the length can be produced, which so far cannot be produced by any other method. Therefore, the findings are to be transferred to more complex profile geometries, i.e. with variable cross-sections or multi-layer structures. Due to the new properties and requirements on the process control, the connected steps stretching and strength increase by artificial ageing have to be adapted. Finally, a detailed investigation of the plastic-aluminium interface of different profiles is carried out for a comprehensive understanding of the process.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr.-Ing. Till Clausmeyer