High strength and toughness die-casting aluminum alloy without heat treatment, preparation method and article thereof

A die-casting aluminum alloy having copper and zinc elements without a heat treatment, comprising the following components in percentage by mass:

• 7.0 wt. %-10.0 wt. % of silicon, no more than 0.05 wt. % of copper, no more than 0.006 wt. % of magnesium, 0.3 wt. %-0.7 wt. % of manganese, 0.1 wt. %-0.2 wt. % of iron, no more than 0.07 wt. % of zinc, 0.03 wt. %-0.2 wt. % of titanium, 0.015 wt. %-0.03 wt. % of strontium, 0.02 wt. %-0.05 wt. % of vanadium, 0.01 wt. %-0.05 wt. % of zirconium, no more than 0.05 wt. % of each of unavoidable impurity elements;
• wherein a sum of the unavoidable impurity elements is no more than 0.25 wt. %, and a rest is aluminum;
• and
• a ratio of the percentage by mass of the vanadium to the percentage by mass of the zirconium is 1.2:1 to 2.4:1, wherein an as-cast tensile strength of the die-casting aluminum alloy is in a range between 270 MPa and 300 MPa, an as-cast yield strength of the die-casting aluminum alloy is in a range between 120 MPa and 150 MPa, and an as-cast elongation of the die-casting aluminum alloy is in a range between 11% and 16%.