Enhanced Corrosion Behavior and Mechanical Properties of Al-Zn-Mg-Cu Sheet Alloy by Ultrasonic Surface Rolling Treatment

An outstanding enhancement of corrosion resistance and mechanical properties of Al-Zn-Mg-Cu alloy was achieved by ultrasonic surface rolling treatment (USRT). The results showed that the precipitates were dissolved into Al matrix, the deformation texture was weakened, and the nanometer/micron/nanometer lamination structure was formed after USRT, which enhanced the corrosion resistance and provided the alloy with an excellent ultimate tensile strength of 578.1 MPa, tensile yield strength of 517.6 MPa and elongation to fracture of 8.5 pct.