Grain refinement under multiple warm compression in an Al-Mg-Sc alloy

Grain refinement taking place in a 1570 aluminum alloy was studied in multiple compression at a temperature of 325degreesC and a strain rate of similar to10(-2)s(-1). Rectangular samples were compressed with consequence change in the loading direction throughout 90degrees from pass to pass. The integrating flow curve shows an extensive flow softening at cumulative strain less than 7 followed by steady-state flow. It was shown that new fine grains with a size of similar to2 mum evolve at strain of similar to2.1. Initially, the recrystallized grains are formed within bands located at an angle of similar to45degrees to compression axis. Following deformation leads to increasing fraction of recrystallized grains. At cumulative strain of similar to12.6, total fraction of recrystallized grains approaches similar to72 pct. Strain localization and uniformity of recrystallized structure during multiple forging are discussed.