Influence of the surface chemistry of Al chips on a friction-induced recycling process for the manufacture of Al wires

• Applicants: Professor Dr.-Ing. Guido Grundmeier; Professor Dr.-Ing. Werner Homberg
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 500288680

The central objective of the project is to investigate the interactions between a specialized chemical pretreatment and the friction-induced recycling process (RIR) or the quality of the semi-finished aluminum products (wire) produced with it. The RIR is based on the Conform process and, due to its quasi-stationary character and the specific tool arrangement, opens up ideal conditions for combined and interdependent chemical and technological investigations in the above-mentioned context. From the point of view of forming technology, the starting material (in particular aluminum chips) and its changes in the extrusion channel must be characterized and described as a model. The process and the result of the RIR are sustainably determined by the surface formation of the starting material. From a chemical point of view, it is therefore necessary to determine the correlation of the oxide structure and adsorbates with the forming internal interfaces of the aluminum alloy as well as to integrate an interfacial chemical process for the targeted pretreatment of the chips into the recycling process. To achieve the overall objective, the project is divided into individual sub-objectives: • Detailed technological investigation of the processes in the extrusion channel or, in particular, in the chip compaction zone, including suitable modeling depending, among other things, on the type, size and surface formation of the starting material (aluminum chips). • Monomolecular functionalization with simultaneous control of the oxide layer thickness of the aluminum chips • Modeling of the influence of the surface chemistry of the chips on the composition of the pressure weld zones in the generated alloy • Conceptual design and construction of an integrated test rig for the RIR of chemically preconditioned and residue- and oxide-free chips • Verification of the function of the integrated test rig and detailed characterization of the semi-finished product properties or the influences and interactions with the chemical and forming influencing parameters.

• DFG Programme: Research Grants