Influence of the mechanical processing of the surface layer by deep rolling on the fatigue strength of aluminum bodies manufactured additively by welding

• Applicants: Professor Dr. Bernd Breidenstein; Professor Dr.-Ing. Jonas Hensel
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing ; Metal-Cutting and Abrasive Manufacturing Engineering
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 522242423

Additive manufacturing processes with powder and wire-based starting materials are becoming more and more common in industry, as additive manufacturing can save material and allows a high degree of freedom in the design of components. Wire-based processes enable high build rates with easy handling of the starting materials. However, this wire-based production leads to high shape deviations, which means that the final contour or individual functional surfaces have to be machined afterwards. In order to expand the knowledge of the interaction between welding process, filler material, heat treatment and machining as well as their influence on the surface properties of the components, the entire process chain must be considered. For this purpose, the conditions after each process step are characterised and digitalised by means of residual stress measurement, topography measurement, microindentation and computer tomography in order to generate numerical models from the measurement data in parallel to the empirical investigations. Finally, the mechanical-technological component properties after the individual process steps of the additive-subtractive process chain and their influence on the fatigue strength are investigated simulative and experimentally. Based on the findings, the influences of the individual process steps on the fatigue strength can be estimated. The originality of the project is characterised by the expansion of the knowledge of the mechanisms of action of the individual steps during the additive-subtractive process chain on the edge zone properties of the components.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr.-Ing. Berend Denkena