Low-pressure die casting is the perfect alternative to high-pressure die-casting, sand casting, and permanent mold casting. In low pressure aluminum die casting process, melted metal is poured into the die at low pressures. The pressure in this operation ranges from 25-150 kPa (3.5-20 psi), much lower than traditional casting methods. Low-pressure die casting results in superior surface finish, dimensional accuracy, and reduced porosity.
The advantages of low-pressure aluminum die casting
There are several advantages of low-pressure aluminum die casting compared to other casting methods. Here are a few:
- Better surface finish: Low-pressure die casting results in superior surface finish compared to other casting methods. This is because the metal flow rate is slow which eliminates turbulence and reduces air entrainment.
- Reduced porosity: Porosity can be a problem with traditional casting methods but is less of an issue with low-pressure die casting. This is because the low-pressure reduces the potential for trapped gas.
- Dimensional accuracy: Low-pressure die casting also provides more dimensional accuracy. The pressure used in this casting method ensures that the metal fills every corner of the die resulting in error-free parts.
- Cost-effective: Low-pressure die casting uses less metal than sand casting and permanent mold casting, making it a cost-effective option.
The low-pressure aluminum die casting process
Low-pressure aluminium die casting consists of four main stages:
- Filling: Molten metal is poured into a holding chamber within the casting machine where it is heated to the correct temperature.
- Injection: Once the holding chamber is filled with molten metal, the die is closed, and the pressure in the chamber is reduced to just above atmospheric. This forces molten metal into the die cavity via a tube.
- Solidification: The molten metal cools and solidifies once it has filled the die cavity, taking on the shape of the mold.
- Ejection: Once the metal has solidified in the mold, it is removed and cleaned to reveal the final product.
Conclusion
Low-pressure aluminum die casting is an excellent option for precision casting of complex parts that cannot be manufactured using other methods. The advantages of this method are many, including better surface finish, reduced porosity, dimensional accuracy, and cost-effectiveness. These benefits make low-pressure aluminum die casting a great choice for manufacturers who want to produce high-quality parts at a lower cost.