Influence of punch velocity on friction behavior in micro deep drawing process

• Applicant: Professor Dr.-Ing. Frank Vollertsen
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing ; Production Automation and Assembly Technology
• Term: from 2010 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 161472980

In macro forming it is already known, that the punch velocity has an influence on the deep drawing process. This influence is considerably induced by the velocity dependent friction behavior between sample and tool. In the micro range new possibilities in process control open up due to small dimensions of components. High dynamic forming machines and a specific optimization of punch velocity are also interesting for industrial applications. Due to the tribological size effects it is expected, that an increasing ratio of opened to closed lubrication pockets will lead to an increasing dry friction in micro range. Therefore, the goal of this research project it is to analyze the tribological size effect on drawing speed dependent friction behavior for micro deep drawing. Based on the working hypothesis, that the friction coefficient is considerably influenced by drawing speed, contact pressure and peculiarity of contact area, the influence of the punch width shall be analyzed. Scaled strip drawing tests with double deflection are to be conducted with a punch velocity range from 1 to 1000 mm/s. In conjunction with results from first phase, an advanced friction model can be described. After successful validation of the friction model, it is supposed to support finding the best drawing speed in micro deep drawing to minimize friction and specimen.

• DFG Programme: Research Grants