Cu-containing high-strength corrosion-resistant Al-Mg-Si alloy and preparation method thereof

[0023] A low-content Cu alloy ingot was prepared. The mass fraction of each alloy element was Mg, 0.9%; Si, 1.5%; Cu, 0.2%; Mn, 0.4%; Er, 0.15%; Aluminum alloy ingots are cut and milled. The ingot is subjected to two-stage homogenization heat treatment. The two-stage homogenization process is: the first stage is kept at 300 °C for 8-12 hours; the second stage is kept at 535 °C for 12 hours. After the ingot undergoes homogenization heat treatment, it is then subjected to hot rolling deformation with 85% of the total deformation at a homogenization temperature of 535° C., and air-cooled to room temperature. The hot-deformed alloy was solution treated at 545°C for 30 minutes, water quenched, and aged at 155°C for 10 hours. Further preferably, the solution treatment at 545 °C for 30 min is immediately followed by water quenching, and then the alloy is immediately aged at 155 °C for 10 h.

[0024] The sheet of Example 1 was processed into a tensile specimen along the rolling dire...

[0026] A medium-content Cu alloy ingot was prepared. The mass fraction of each alloy element was Mg, 0.9%; Si, 1.5%; Cu, 0.4%; Mn, 0.4%; Er, 0.15%; Zr, 0.15%, and the balance was Al, which The steps are the same as in Example 1, and the tensile test results are listed in 1.

[0028] A high-content Cu alloy ingot was prepared. The mass fraction of each alloy element was Mg, 0.9%; Si, 1.5%; Cu, 0.6%; Mn, 0.4%; Er, 0.15%; The steps are the same as in Example 1, and the tensile test results are listed in 1.