gravity die casting

Throughout this blog key facts regarding gravity die casting, also known as permanent moulding or chill casting, will be discussed. The process is used to form complexly shaped components, largely for industrial applications. Gravity die casting is most commonly used within medical, defence and energy sectors.

What is Die Casting?

Die casting is a metal casting process that is distinguished by injecting molten metal under high pressure into a mould cavity. The process is used to produce finished parts.

Why Does Die Casting Matter?

Although you may be blissfully unaware of its importance, it is difficult to imagine the world we see today without the use of die casting. Die casting is widely recognised as one of the most efficient methods of producing high-quality parts. The manufacturing of anything from your iPhone case to car parts utilises the die casting process!

Metals Used in Gravity Die Casting

The main materials that are used in die casting alloys are zinc, lead, tin, copper, magnesium and aluminium. In the early years of the process, tin and lead were the first metals that were used. Differently, in modern die casting, aluminium is the most readily used- accounting for more than 80% of all die-cast parts.

Interesting Facts About Gravity Die Casting

Cast Iron

Cast iron is the predominant material used for ‘dies’ in gravity die casting. The die generally has two components, one part able to move and one part fixed in position. In some cases, steel pins are included to assist with the ejection of the casting at the conclusion of the process.

The separate halves of the die are heated and sprayed with insulation and lubricant layer prior to being clamped together. This coating lubricates the moving parts and reduces any potential wear on the dies.

Intricate Patterns

Inserts, usually manufactured by metal or sand, can then be implemented into the die to produce internal features. Upon its completion, molten metal can be poured into the die cavity.


Just like the name of the process suggests, gravity is the only force required to fill the die cavity. Differently, during high-pressure die casting, additional pressure is required.

Repetition is Key

Although the initial cost for gravity die casting is high, the dies used in gravity die casting can last for a number of years making it the cost-effective decision for those dealing with large production.

Casting Defects

Much like most casting methods, die casts can succumb to varying defects including cold shuts, misruns and inclusions. When it comes to gravity die casting, sand burn is not an issue, a problem frequently apparent in sand casting.


gravity die casting

If comparing die casting to sand casting, the differing characteristics of metal dies and sand moulds have an effect on the cooling process. The molten metal cools quicker using gravity die casting compared to sand casting as metal is denser than sand.


As the molten metal solidifies so quickly, the production process is much quicker, and hundreds of castings can be manufactured each day. The increased production speed provides a distinct advantage over sand casting.

No Job too Small

Gravity Die Casting is the ideal production process for producing the smallest of metal parts. The differing projects we have undertaken may surprise you. Gravity Die casting is known for producing a high-quality product when compared to alternative methods. However, with the invention of new sand bonding methods, sand casting and gravity die casting can now produce similar standards of complexity in the finished product.

Environmentally Friendly

A major benefit to the gravity die casting process is that it is environmentally friendly. One of the simplest methods of reducing car pollution is making their engines smaller, and in turn, their cars lighter. To do this, automakers worldwide are increasing the number of die castings in their vehicles to make them more efficient. If that wasn’t enough, die casting products are also 100% recyclable.

In essence, gravity die casting is one of the age-old processes for producing small metal products and continues to be one of the most efficient, cost-effective choice when large quantities are involved. If you’re interested in finding out more about gravity die casting, contact one of our experts on 01282 422361.

Lupton & Place