RWTH Aachen, Institut für Bildsame Formgebung (Aachen, Germany):

Schwich G., Mag. Eng., e-mail: schwich@ibf.rwth-aachen.de
Seitz J., Mag. Eng.
Hirt G., Dr. Eng., Prof.

University of Cambridge (Cambridge, UK):

Jenkouk V., Mag. Eng., Dept. of Engineering

Ring rolling is an incremental bulk forming process for the near-net-shape production of seamless rings. This paper shows how nowadays the process design and optimization can be efficiently supported by simulation methods. Schematic diagram of the axial profiling displays ring rolling operating steps, including positioning of the laser measuring system. Experimental and simulation results are compared and presented in the paper, as well as comparison between outer diameter and radial force both in experiment and simulation. Development of recrystallized fraction, average grain size and recrystallization time are displayed. For reliable predictions of the material flow and the microstructure evolution it’s necessary to include a real ring rolling mill’s control algorithm into the model. Furthermore, an approach for the online measurement of the profile evolution during the process is presented by means of axial profi ling in ring rolling. Hence the defi nition of new ring rolling strategies it is possible even to provide advanced geometries, sufficient quality level and manufacture of shapes that could not be produced before with repeatable results. Using a linear laser helps to get important information about variation of geometric parameters. Material consumption can be cut by 25% comparing with conventional production processes, while expenses for mechanical processing — by 80%.

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