A 7XXX aluminum
alloy profile comprises the following components: less than or equal to 0.1% of Si, less than or equal to 0.1% of Fe, 0.5%-0.55% of Cu, less than or equal to 0.1% of Mn, 2.3%-2.6% of Mg, 7.1%-7.5% of Zn, 0.05%-0.1% of Zr, less than or equal to 0.05% of Ti, 0.05%-0.1% of Er and the balance of aluminum and other inevitable
impurity elements, the content of each of other elements is less than or equal to 0.05%, and the total content is less than or equal to 0.15%. The preparation process of the on-line water-cooling shaping-free 7XXX aluminum
alloy comprises the following steps: proportioning according to the
mass fraction,
smelting the aluminum
alloy, refining, standing,
casting, homogenizing a cast
ingot, extruding a sectional material, cooling the sectional material, stretching the sectional material, aging the sectional material and measuring the flatness. The aluminum alloy section manufactured through the
manufacturing technology has good yield strength, the yield strength can exceed 530 Mpa, the
ductility can reach 10% or above, in the
machining process, the 7XXX aluminum alloy can reach a plane without manual shaping after being subjected to water-cooling straightening, production can be conducted at a high speed,
extrusion defects do not occur, and the product quality is improved. The
mechanical property of the material is further improved.