Die-casting aluminum alloy has good performance and process performance. Therefore, the rapid development of die-casting of aluminum alloy is widely used in various industrial sectors. The amount is much higher than other non-ferrous alloys, and it occupies an extremely important position in die-casting production.

Aluminum alloys are divided into Al-Si alloy, Al-Cu alloy, Al-Mg alloy, and Al-Zn alloy.

1. Al-Si alloy

Because the eutectic Al-Si alloy has the characteristics of small crystallization temperature interval, large solidification latent heat and large specific heat capacity of the silicon phase in the alloy, and its linear shrinkage coefficient is also relatively small, its casting performance is generally better than that of other aluminum alloys. Good, its filling performance is also good, and the tendency of thermal cracking and shrinkage is relatively small.

2. Al-Mg alloy

The performance characteristics of Al-Mg alloy are: good mechanical properties at room temperature; strong corrosion resistance; poor casting performance; fluctuations in mechanical properties and wall thickness effects are relatively large; long-term use will cause the plasticity of the alloy to decrease due to aging , Even die-casting parts appear cracking; die-casting parts have a greater tendency to produce stress corrosion cracking.

3. Al-Zn alloy

Al-Zn alloy die castings can obtain high mechanical properties after natural aging. When the zinc mass fraction is greater than 10%, the strength is significantly improved. The disadvantages of this alloy are poor corrosion resistance, stress corrosion tendency, and easy thermal cracking during die casting.

4. Die-cast aluminum alloy with special properties

Die-cast aluminum alloys with special properties developed at home and abroad include:

Decorative Al-Mn alloy: suitable for anodic oxidation treatment and coloring treatment, high elongation, but also has considerable corrosion resistance. But its strength is not high, the shrinkage rate is large, and it is easy to stick to the mold.

Heat-treated Al-Si-Cu alloy: It can be incompletely artificially aged after quenching and fully artificially aged after quenching to the maximum hardness.

In addition, there are Al-Mn-Zn alloys with combined surface treatment and heat treatment, wear-resistant hypereutectic Al-Si alloys, and explosion-proof and vibration-proof Al-Zn alloys.

In addition, there are die-cast aluminum alloy composite materials, which have not yet been widely produced and applied.