The effect of rolling on the microstructure and compression behavior of AA5083 subjected to large-scale ECAE

Abstract

In the present work, an aluminum alloy AA5083 that went through equal channel angular extrusion (ECAE) was further processed with rolling under two different conditions. Mechanical examination on both as-ECAE and ECAE + Rolling samples suggests that such post-ECAE processes can further effectively enhance the strength of the alloy. The underlying mechanisms were investigated with the assistance of microstructural examination using transmission electron microscopy (TEM). Precipitates of two morphologies were found in the alloys with dimensions ranging from a few to hundreds of nanometers. These precipitates were determined to have a minor effect on the strength differences between the alloys with or without post-ECAE rolling. However, the work hardening caused by the high number of dislocations accumulated inside the grains and the concomitant grain size reduction along the normal direction (ND) due to plate thickness reduction were considered as the primary reasons for the strength increase in the post-ECAE rolled AA5083.