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Features of zinc alloy: High density. It has good casting properties, enabling the die-casting of precision parts with complex shapes and thin walls, and the cast surfaces are smooth. Surface treatment is available: plating, spraying, painting. It does not attract iron during melting and die-casting, does not corrode the molded parts, and does not stick to the molds. It has excellent mechanical properties and wear resistance at room temperature. It has a low melting point, melting at 385°C, and is easy to mold by die casting. Points to note during use: (Poor corrosion resistance) When impurity elements such as lead, cadmium, and tin in the alloy composition exceed the specified limits, it causes the casting to age and deform, resulting in an increase in volume and a significant decline in mechanical properties, especially plasticity; over time, the casting may even crack. Lead, tin, and cadmium have very low solubility in zinc alloys; as a result, they accumulate at the grain boundaries and act as cathodes, while the aluminum-rich solid solutions serve as anodes. In the presence of water vapor (the electrolyte), this leads to intergranular electrochemical corrosion. Die-cast parts age due to intergranular corrosion. (Ageing effect) The microstructure of zinc alloys is mainly composed of zinc-rich solid solutions containing Al and Cu, and aluminum-rich solid solutions containing Zn; their solubility decreases as the temperature drops. However, due to the extremely fast solidification rate of die-cast parts, by the time they reach room temperature, the solubility of the solid solution is **completely saturated**. After a certain period of time, this supersaturation phenomenon gradually dissipates, causing slight changes in the shape and size of the casting. (Temperature effect) Zinc alloy die-cast parts should not be used in working environments with high temperatures or low temperatures (below 0°C). Zinc alloys possess good mechanical properties at room temperature. However, both the tensile strength at high temperatures and the impact performance at low temperatures decrease significantly. Zinc alloy type Zamak 3: Good flowability and mechanical properties. It is used for castings where mechanical strength requirements are not high, such as toys, lighting fixtures, decorations, and certain electrical components. Zamak 5: Good flowability and good mechanical properties. Zamak 2: Used for mechanical parts that require special mechanical properties, high hardness, and moderate dimensional accuracy. ZA8: Good flowability and dimensional stability, but poor fluidity. It is used for die-casting workpieces that are small in size and require high precision and mechanical strength, such as electrical components. It offers the best fluidity and is used for die-casting thin-walled, large-sized parts with high precision and complex shapes, such as electrical components and their enclosures. Different zinc alloys have various physical and mechanical properties, which provides options for the design of die-cast parts. Superloy: Offers the best liquidity, and is used for die-casting thin-walled, large-sized components with high precision and complex shapes, such as electrical components and their enclosures. Different zinc alloys have various physical and mechanical properties, which provides options for the design of die-cast parts.