Optimizing Solution Heat Treatment to Improve Mechanical Properties of Al Alloy 7055

The influence of one- and two- stage solution heat treatment on the microstructure and mechanical properties of aluminum alloy 7055 was investigated. The results showed that in the case of one-stage solution heat treatment in the range of 450 °C to 470 °C, the strength increased while the ductility decreased with temperature. Further increasing temperature led to more dissolution of soluble constituents but a large amount of recrystallization, therefore, the strength decreased while ductility increased. The two-stage solution heat treatment, which included first stage of low-temperature-long-duration and second stage of high-temperature-short-duration heating was suggested for improvement of mechanical properties.