Formability of Ultrafine-Grained AA6016 Sheets Processed by Accumulative Roll Bonding

Abstract:

Aluminium alloy AA6016 was accumulative roll bonded up to eight cycles in order to produce an ultrafine-grained microstructure. The formability of these sheets was investigated by means of bending tests. Furthermore the influence of a local laser heat treatment at the bending edge is observed. The strength of the UFG samples is increased by a factor of around two compared to the conventionally grained T4 condition which also results in up to 50 % higher punch forces needed for bending of ARB processed samples. An anisotropic bending behaviour is observed. By applying a tailored laser heat treatment along the bending edge prior to the bending tests a local recrystallization and recovery at the deformation zone of the samples is achieved. Thus, ductility is increased locally whereby bending to an angle of 80° is possible with lower forming forces compared to the non-heat treated specimens. The results are compared to previous studies on mechanical properties and formability investigations of ARB processed AA6016.

• Periodical: Key Engineering Materials (Volumes 504-506)
• Pages: 575-580
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.504-506.575
• Online since: February 2012
• Authors: Tina Hausöl, Christian W. Schmidt, Verena Maier, Wolfgang Böhm, Hung Nguyen, Marion Merklein, Heinz Werner Höppel, Mathias Göken
• Keywords: Accumulative Roll Bonding (ARB), Bending, Formability, Nanoindentation, Tailored Heat-Treatment, Ultrafine Grained Microstructure

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