Types of Die Casting Processes

A metal casting process used in most manufacturing processes, die casting offers an efficient and cost-effective method to produce large volumes of high-quality products. This technique is used in the manufacture of small to mid-sized metal spare parts. Die casting is basically a simple process that involves pouring molten metal into a pre-designed cast. As the metal solidifies, it moulds into the shape of the cast, which can then be easily removed from the cast and used. The important factors that determine the quality of the finished product of die casting are the raw material, temperature, solidification time and die casting process. The two popular metal alloys used for die casting are zinc alloy and aluminium.

Let’s take a look at the different processes of die casting and how they affect the quality of finished product.

Cold-Chamber Die Casting Process

This process is commonly used for aluminium die casting. In this method, metal alloy is first melted in a furnace, and then it is manually or automatically poured into the injection system, which then passes on to the cast. It is a very slow method, which may be its only disadvantage. But, on the other hand, this technique is very effective for corrosive applications and for casting metal alloys with high melting points.

Hot-Chamber Die Casting Process

Also known as gooseneck casting, the hot-chamber die casting process is popularly used in most manufacturing units. It is called as gooseneck casting process because the technique involves the injected molten metal flowing through a gooseneck feed system into the cavity of the cast. This technique is best suited for metal alloys with high fluidity and low melting point. It is most commonly used for zinc metal casting, though other metals such as copper, lead and magnesium are also cast using this technique.

Low-Pressure Die Casting Process

This aluminium die casting technique is used when large volumes of parts have to be manufactured. In this process the mould is placed above the metal bath, and a riser tube connects the two. Pressure is applied in the chamber, which pushes the molten metal towards the cast on top.

Vacuum Die Casting Process

A die casting process similar to low-pressure die casting, this technique involves creating a vacuum in the cavity to force the molten metal into the riser tube and the cast placed on top. An advantage of this technique is that it prevents the formation of gas inclusions during the zinc die casting process.

Aluminium Die Casting – Efficient, Durable and Versatile

Metal die casting is a process that is being used in a number of industries for efficient and effective product manufacturing. This process involves melting a metal and forcing it to pass through cavities or chambers at high pressure and then allowed to cool. After the metal cools, it takes up the shape of the die cast. This method reduces time and effort required in manufacturing a number of products. Though a number of non-ferrous materials are used in die casting, aluminium is generally preferred in a range of applications.

There are many benefits of using aluminium die castings. First, this metal is lightweight and is highly corrosion resistant, which makes it suitable for use in a variety of applications. Moreover aluminium is strong, stiff, hard and has a high strength to wait ratio. All the features make it highly suitable for use in automobile part manufacturing. Its high thermal and electrical conductivity make aluminium a great choice for telecom and computing industries. These attributes also make this metal perfect for use in electrical housings and connectors. Above all, aluminium has good EMI and RFI shielding properties, so it is suitable for use in the manufacture of handheld devices. Plus, aluminium retains its strength even at very high temperatures. So, even if it is melted and then cooled, it will not lose its original attributes. All these features make this metal perfect for die casting.

There are basically two methods used for die casting - hot chamber or cold chamber. While die casting aluminium, the cold chamber method is preferred over the hot chamber method as aluminium may react with iron when it is heated to a very high temperature. In the high pressure aluminium die casting, a separate chamber is used to melt the metal. When the metal alloy reaches the molten stage, the required amount is slowly transferred into the cold chamber, and into the hydraulic piston. Using this technique, high number of casts with high-quality casts can be produced over time. Different types of aluminium alloys are used in various manufacturing processes. The most commonly used alloys are A380, 413 and 383.

High pressure aluminium die casting is a versatile technique that is not only efficient, but also allows manufacturers to design and create high-quality durable die casts.