Extrusion of hollow profiles with tailored wall thicknesses

• Applicant: Privatdozent Dr.-Ing. Sören Müller
• Subject Area: Metallurgical, Thermal and Thermomechanical Treatment of Materials ; Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2011 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 201590891

Aluminum hollow profiles are often used for lightweight applications in automotive and aviation industries. Since the load distribution is not constant over the profile length the wall thickness needs to be designed according to the maximum load. In order to avoid oversizing it is desirable to increase the wall thickness in high stressed areas only. Other parts of the profile can be designed with smaller wall thickness. In the requested project the profile cross section will be varied by using an axially moving mandrel in a porthole die. This leads to a complex material flow. The requested project aims at the investigation of the influence of this complex and for the varied wall thicknesses different material flow on microstructure and mechanical properties of the profiles. For that purpose after designing and constructing the needed tools, extrusion experiments will be conducted using different temperatures and velocities. The effect of the material flow on size accuracy will be studied by measuring the dimensions of the extruded profiles and comparison with predictions from FEM-simulations. Finally, significant profile sections will be characterized according to microstructure and mechanical properties.

• DFG Programme: Research Grants