The invention relates to 7XXX aluminum
alloy. The 7XXX aluminum
alloy comprises the following components by weight percent: 6.6 to 7.6 percent of
zinc, 1.25 to 1.80 percent of
magnesium, 0.18 to 0.44 percent of
copper, less than or equal to 0.06 percent of
silicon, less than or equal to 0.16 percent of iron, , less than or equal to 0.03 percent of
manganese, less than or equal to 0.03 percent of
chromium, less than or equal to 0.02 percent of
germanium, less than or equal to 0.02 percent of
vanadium, less than or equal to 0.03 percent of
titanium, less than or equal to 0.02 percent of
zirconium, and less than or equal to 0.03 percent of total weight of
manganese and
chromium, less than or equal to 0.03 percent of each rest
impurity element, less than or equal to 0.10 percent of total weight of rest
impurity elements, and the balance of aluminum. On the basis of experiment, the material strength is improved by re-designing the
mass fraction and a ratio of Zn to Mg; by re-designing the
mass fraction of Cu, the
alloy has excellent
corrosion resistance, and the oxidation different color problem of silver white can be solved. By strictly controlling the weight percent of the
impurity elements such as Mn and Cr, the
crystal grains of the alloy material are uniform. Compared with the existing disclosed Al-Zn alloy
system, the alloy has better comprehensive performance, and an oxidized membrane formed by oxidizing the material by virtue of
anode is more delicate and beautiful.