Influence of ECAP and age hardening treatment in 6061 Al alloy

In the present work, ECA pressing is used to deform a commercial 6061 Al (T6 condition) alloy to very large strains. An ultrafine grained structure has been formed by the fragmentation of the original grains, after one pass and after four passes the structure becomes more uniform. The results show the presence of precipitates from the Al-Mg-Si system. Peak ageing values increase with the number of passes because the density of precipitates increases with the number of passes through fine distribution of precipitates, and the precipitates become smaller with grain refinement. The aim of the present paper is to demonstrate the efficiency of this technique to form ultrafine grained structure and the influence of ECAP on peak ageing structure.