Identification of the mechanisms of action of the tribological behaviour of structured semi-finished product surfaces during full forward extrusion of aluminum alloys with regard to friction and wear reduction (TriboLub)

• Applicant: Professor Dr.-Ing. Thomas Bergs
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 460819047

Due to its high material efficiency, cold forming offers a particularly energy- and resource-efficient production method for near-net-shape components in large quantities. However, the high tribological loads during forming lead to wear on the tools. In order to reduce tool wear, workpieces’ surfaces are often structured by shot peening or electrochemical etching. The structures act as lubricant pockets when lubricant is used. Their geometry influences the contact mechanics in the effective joint by hydrostatic and hydrodynamic effects. These effects can lead to a local improvement in friction and wear. The effects of lubricant pockets on the tribological system as a function of their geometries have not been sufficiently researched according to the current state of the art in the field of full forward extrusion of aluminum alloys. The challenge is consequently to design lubricant pockets produced by shot peening and electrochemical etching in such a way that friction and wear are reduced. Therefore, the aim of this project is to identify the mechanisms of action of the workpiece structuring on the tribological system. The project is based on the hypothesis that the analysis of the tribological system influenced by lubricant pockets provides information about the existing hydromechanical and contact mechanisms through the quantification of friction and wear. To conduct the project, a combined approach of numerical and experimental investigations is planned to investigate the suitability of different shot peening media and their combinations with electrochemical etching for workpiece structuring for full forward extrusion of aluminum.

• DFG Programme: Research Grants