Abstract: There is disclosed an improved memory disk stock comprised of an alloy composition which includes: about 1-11 wt. % magnesium, preferably between about 2-7 wt. % Mg; up to about 0.3 wt. % zirconium preferably about 0.02-0.25 wt. % Zr; up to about 0.2 wt. % iron, up to about 0.2 wt. % silicon, and about 0.02-0.2 wt. % of a dispersoid-forming element selected from scandium, erbium, thulium, lutetium, ytterbium, hafnium and yttrium, the balance aluminum and incidental elements and impurities. With preferably about 0.05-0.15 wt. % of scandium added to such compositions, these disk stocks exhibit significant room temperature yield strength increases over the same compositions without any scandium added.