For Al Zn alloy, due to the large solubility of Zn in Al, when the mass fraction of Zn in Al is more than 10%, the strength of the alloy can be significantly improved. Although this kind of alloy has a large natural aging tendency and can obtain high strength without heat treatment, the disadvantages of this kind of alloy are poor corrosion resistance, high density and easy to produce hot cracks during casting. Therefore, this kind of alloy is mainly used to manufacture die casting instrument shell parts.