various alloying elements in 7075 T6 aluminum alloy bar can also affect the strength and hardness. For example, copper element can improve the strength and corrosion resistance of the alloy, and magnesium element can improve the strength and hardness of the alloy while reducing the corrosion resistance of the alloy. Elements such as manganese, chromium, and titanium can also have a positive impact on the properties of the alloy. After solution treatment and aging treatment, the strength and hardness of 7075-T6 aluminum alloy have been significantly improved. Solid solution treatment is to heat the alloy to a certain temperature to fully diffuse the various elements in the alloy and form a supersaturated solid solution.