The effect of cryogenic deformation on the properties of 7050 aluminum alloy

The precipitation hardenable 7xxx series aluminum alloys are extensively used in automotive and aviation industry. Although the studies on 7075 series alloys are prominent in the literature, 7050 series alloys have better fracture toughness and resistance to stress corrosion. In the scope of this study, the effect of cryorolling on the mechanical properties and microstructure after ageing of precipitation hardenable 7050 aluminum alloy has been characterized with hardness measurements and SEM analysis, respectively. With this purpose, the plates, which have been solution treated at 470°C for 1 hour, were subjected to %5-20 deformation by cryorolling. As a result of aging at 120 ° C for varying time periods, no significant change was observed in the maximum hardness of the alloy after deformation while the peak aging time decreased with increasing amount of deformation. The decrease in peak aging time, which is an important parameter for production speed, was attributed to the increased nucleation rate due to the high density of dislocations.