FOR 922:  Development of an In-process Material Model of Light Metal Extrusion for the Continuous Optimisation of the Process Chain

• Subject Area: Materials Science and Engineering
• Term: from 2008 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 41469863

Although the extrusion process is widely-used and of great economic importance, yet no numerical model for the modelling of the whole process chain from the tool design through extrusion parameters to the heat treatment exists.
Emphasis of the Research Unit is the development of a methodology that is capable of modelling the whole process chain and that defines the required parameters for the tool geometry, the extrusion parameters and heat treatment, on the basis of the profile geometry and the desired mechanical properties. At the same time, on the basis of these data, the materialising microstructure, the mechanical properties and the expected distortion of the profile shall be predicted by simulation.
For this purpose all steps of the process chain are described mathematically and are exemplarily investigated on small-scale industrial extrusion presses. Investigated are both the direct and the indirect extrusion of one 6xxx wrought alloy and one 7xxx wrought alloy respectively as well as different methods of heat treatment.
In detail the main emphases are:
(1) the characterisation of the microstructure induced by deformation, in particular the recrystallisation behavior, the grain sizes and the allocation of precipitates,
(2) the development of a method for the modelling of the effects taking place in the shearing zone, in particular the mechanical and thermal interactions,
(3) the establishing of novel measuring methods for the determination of changes of the materials properties during the hot ageing of aluminum, e.g. eddy current methods or acoustical measuring methods,
(4) the investigation of the potential of novel gas quenching and spray quenching methods for the reduction of distortion in combination with solution heat treating directly by the extrusion heat or subsequently,
(5) development of a model for the determination of the heat transmission by means of thermal simulation of the continuous quenching process.The implementation of the developed methodology, e.g. by software enterprises, into a commercial software and the spread in the industrial application shall be done directly after the completion of the investigations. Therefore from the very first industrial partners actively collaborate with the Research Unit.

• DFG Programme: Research Units

Projects

• Charakterisierung und Modellierung der Wechselwirkungen beim Strangpressen von Aluminium (Applicant Kammler, Matthias )
• Mikrostrukturentwicklung beim direkten Strangpressen (Applicant Schikorra, Marco )
• Modellierung des Ausscheidungsverhaltens von Aluminiumknetlegierungen (Applicant Bormann, Dirk )
• Simulation und experimentelle Untersuchung verzugsarmer Abschrecktechnologien beim Ausscheidungshärten stranggepresster Aluminiumlegierungen (Applicant Keßler, Olaf )
• Untersuchung und Modellierung einer integrierten Spraykühlung beim Strangpressen mit simulationsbasierter Auslegung des Düsenfeldes (Applicant Schaper, Mirko )
• Zentrale Aufgaben, Koordination, Geschäftsführung, Verwaltung (Applicant Schaper, Mirko )

• Spokesperson: Professor Dr.-Ing. Mirko Schaper