A Pronounced Hardening Response in Non-Heat-Treatable Al-Mg Based 5xxx Aluminum Alloys

The Al-Mg base 5xxx Al alloys are non-heat-treatable. They derive their strength from solid solution and strain hardening. They are, however, supersaturated and this can cause sensitization issues. This work shows that by applying a recently developed cyclic strengthening approach, a high density of Mg-Al clusters can be formed in these materials resulting yield and tensile strengths, and elongations, superior to the precipitation hardened AA6061 (Al-Mg-Si) in the peak aged (T6 state). The implications for categorizations of Al alloys are discussed and future directions of interest are highlighted.