Tool Design Induced Anisotropic Flow Behavior of Hot Extruded Aluminum Profiles

Abstract:

The hot extrusion process may lead to frequently observed textures in the profiles, like fiber structures in longitudinal direction. Aluminum profiles (AA6060) were extruded with different tool types (flat-face dies and modified porthole dies). Compression tests of cylindrical specimens, which were machined out of these profiles likewise in extrusion direction, were conducted to examine possible effects of the in-plane anisotropy in lateral direction. A hardness distribution over the cross section of the specimens was measured. It was found that dependent on tool design and profile geometry, the specimens developed preferred lateral flow directions during upsetting. Simulations of the upsetting test, with assigned Hill parameters to consider anisotropy of the material, showed, that this anisotropy, not the local hardness nonuniformity, is the main reason for the detected plastic flow properties.

• Periodical: Key Engineering Materials (Volume 585)
• Pages: 131-138
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.585.131
• Online since: December 2013
• Authors: Stefan Ossenkemper, Matthias Haase, Celal Soyarslan, Andreas Jäger, A. Erman Tekkaya
• Keywords: Aluminum (Al), Anisotropy, Cold Forging, Flow Behavior, Hot Extrusion

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