Pressure die casting VS Gravity die casting:
Pressure die casting is an automated process in which the metal is injected at high force into the die. It’s a quick, cost-effective and reliable process for a high-volume production and the metal components manufactured through it are net-shaped and have tight tolerances. The molten metal solidifies very quickly and is automatically extracted. This process is capable of producing thousands or millions of components with close consistent dimensional control and thin walls.
Gravity die casting produces good-quality components as well, but it’s best-suited for low to medium volume orders. This process requires the molten metal to be poured into the mould by relying on hydrostatic head height to offer pressure to the casting, with the correct filling of the die being controlled by tilting. This can be a manual process and, although an automatic ladle to pour the metal can also be used, tooling is generally simple and as a consequence is far cheaper than pressure die casting.
Both pressure and gravity die casting are only suitable for alloys with low melting points such as aluminium and zinc. Zinc is the easiest metal to cast and offers a high degree of ductility, high impact strength and a long lifespan. Aluminium is a lightweight material, so it’s perfect for industries where weight is a concern, such as aerospace and automotive. It offers high dimensional stability, good resistance to corrosion and high thermal and electrical conductivity, amongst other properties.
Die casting is a very efficient and versatile process used in metalworking, capable of producing countless varieties of parts used in a wide range of applications and industries. However, it is important to take certain factors into consideration when making the decision between pressure and gravity die casting. These factors include:
The batch and quantities required
The complexity and surface finish of the castings
The wall thickness of the components
The type of material you would like to use
The lead time you need for your project