A novel method simultaneously eliminating Portevin-Le Chatelier effect and enhancing strength in non-heat-treatable Al-Mg alloys

This study investigates the effects of cyclic plasticity on the tensile properties of AA5083 alloys. The low strength and Portevin-Le Chatelier (PLC) effect in Al-Mg alloys means they have found limited use in automotive outer panels. This work shows that by applying cyclic strengthening approach to AA5083, a high density of Mg-Al clusters can be formed in matrix resulting in increased yield and tensile strengths. Moreover, the introduction of cyclic plasticity also effectively suppresses the PLC effect, which is due to the formation of the clusters and the consequent reduction in the number of free Mg atoms in the solid solution. This method introduces the concept of particle strengthening in Al-Mg alloys without altering composition, while simultaneously eliminating the PLC effect. It suggests a potential path for using 5xxx series alloys in applications traditionally dominated by 6xxx series alloys, with added benefits for recycling and sustainability in the automotive industry.