Optimization of the Chemical Composition and Homogenization Treatment of AA7020 Aluminum Alloy
Four variants of AA7020 aluminum alloy having different Zr and Cr contents were investigated aiming at reaching high recrystallization resistance during and after hot deformation. Isothermal homogenization treatments were performed at temperatures of 390-550 °C for 2 to 48 hours. The uni-axial hot compression tests were conducted at 450 °C and strain rate of 10 s-1 at a strain of 0.6. Thereafter, the samples were annealed at 550 °C for 10 min. It was found that the samples with the highest Zr and Cr contents showed the lowest volume fraction of recrystallized grains which was attributed to the highest volume fraction of Zr- and Cr-containing dispersoids formed during homogenization. The optimum homogenization treatment to achieve highest recrystallization resistance for these samples was 470 °C for 24 hours.
T. Chandra, N. Wanderka, W. Reimers , M. Ionescu
A. R. Eivani et al., "Optimization of the Chemical Composition and Homogenization Treatment of AA7020 Aluminum Alloy", Advanced Materials Research, Vols. 89-91, pp. 177-183, 2010