High strain rate superplasticity in continuous cast Al-Mg alloys prepared via friction stir processing

Friction stir processing (FSP) is very effective in refining the grain size of as-cast alloys. In this work, the effect of five FSP conditions on the high-temperature deformation properties of a continuous cast Al-Mg alloy has been investigated. It was observed that FSP broke down the cast structure and refined the grain size to less than 3 pm, enabling tensile elongation of over 800% at 530 degrees C with a strain rate of 3 x 10(-2) s(-1). (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.