The cyclic stress-strain response of polycrystalline AlZnMg alloy and commercial alloys based on this system

An investigation of cyclic response has been made of pure AlZnMg ternary alloy, heat treated by two methods so as to produce shearable and non- shearable precipitates, and two commercial alloys based on this system. A particular feature of the investigation was the measurement of cyclic stress-strain curves at very low strains not hitherto reported for aluminum-based commercial alloys. Plateaux have not been observed in the cyclic stress-strain curves of any of these alloys. The AlZnMg alloy was found to be cyclically stable for both heat treatments, and the constituent and dispersoid particles in the commercial alloys also helped to suppress any evidence of strain localization in the cyclic stress-strain curves. Life measurements for these alloys are also reported.