Surface modification method for improving stress corrosion resistance of 7075-T6 aluminum alloy

The invention discloses a surface modification method for improving stress corrosion resistance of 7075-T6 aluminum alloy. The surface modification method comprises the following steps: 1) clamping a 7075-T6 aluminum alloy workpiece on a supporting device; and (2) the 7075-T6 aluminum alloy workpiece is driven by a supporting device to rotate, and meanwhile, the surface layer of the 7075-T6 aluminum alloy is subjected to ultrasonic impact rolling treatment through an ultrasonic rolling device moving in the axial direction of the 7075-T6 aluminum alloy workpiece. According to the method, the stress corrosion resistance of the 7075-T6 aluminum alloy is improved by utilizing an ultrasonic surface rolling technology, and the surface smoothness of the 7075-T6 aluminum alloy is also improved while a gradient nanostructure is prepared in the alloy, so that the stress corrosion resistance of the aluminum alloy reaches a good state; unification of excellent stress corrosion resistance and high strength and plasticity