Exploring Hot and Cold Chamber Die Casting: Types, Applications, and Advantages

Today I will be discussing different types of die casting and their applications. Die casting is known to be a metalworking process that is carryout by forcing metals or alloys in a mold cavity at a very high temperature. If you can recall from my previous article, the die casting process is utilized when bulk metallic parts are needed.  That is, it offers a fast production rate. As for the types of the die casting process, there are two types which include hot and cold chamber.

Types of die casting process

Hot chamber die casting

The hot chamber is the most popular type of die casting. it is also known as gooseneck casting. In the hot chamber, the casting chamber is constantly in contact with a liquid alloy and molten metal passes through a valve into the casting chamber. Piston also plays an important role. It helps to press the molten metal in the chamber at high speed. Hot chamber types of die casting are suitable for casting metals with low melting points and fluidity e.g. copper, magnesium, zinc, tin, lead, etc. one of the greatest advantages is that, direct immersion helps to quickly transfer molten metal into a mold cavity.

Cold chamber die casting

In these types of die casting, immersion of the injection mechanism in the molten bath is eliminated. Molten metal is automatically or manually pour into an injection system in a cold chamber. It is carryout by filling a casting chamber with alloy and pressing it to pass through channels to the die casting mold. Unlike hot chamber, cold chamber dies casting is suitable for metals with a higher melting point,s for example, aluminum and copper. This is because of the corrosive nature of the metals, making them not suitable for immersion in hot chamber die casting.

Different variations can be implied in any of these types of die casting when producing items. These include:

Low pressure dies casting:

Low pressure uses metals or alloys with low melting points. It has the possibility of casting components from 2 to 150kg, offering high strength and complex geometry. It also improves dimensional accuracy and material utilization. However, low-pressure die casting is not suitable for an item with a tin wall, because the minimum wall thickness that can be obtained is 30mm. it is a slower process.

High-pressure die casting:

It is a process in which molten metal is forced under pressure into a lock metal die cavity, where it is held by a powerful press until the metal solidifies. After solidification of the metal, the die is unlocked, opened, and the casting ejected.

Other processes include:

Vacuum  process:

This process is a new process that offers good strength and minimal porosity to the casting. It is similar to low-pressure die casting, except for the arrangement of die casting mold and molten metal bath. The vacuum here is a cylinder chamber, which helps in forcing molten metal into a mold cavity. these types of casting are carryout on items having post-casting heat treatment uses.

Squeeze die casting:

Squeeze die casting is established as a working solution for casting metals and alloys with low fluidity. It is carryout by filling molten metal in an open die. The die is squeeze closed, forcing metal into a mold cavity. these types of die casting are often used for strengthening fiber and are mostly related to molten aluminum. It produces a good dense product.

Semi-solid die casting:

This process is also known as thermoforming. It offers maximum density and minimum porosity just as of the squeeze process. Materials are cut into smaller slags before heating. After heating to a phase transition between solid and liquid, it is forced into a mold cavity. Nonferrous metals are often used e.g. magnesium alloy and aluminum alloy.

Applications of die casting

As die casting is used for large series of production and its applications in many industries such as aerospace, domestic appliances, furniture, power tools, electronics, machinery, lighting technology, etc.

Die casting is also applicable in automotive industries in producing wheels, blocks, cylinder heads, valves, and manifolds.

That is all for this post, where the applications and types of die casting are discussed. I hope you enjoyed the reading, if so, kindly share with other students. Thanks for reading, see you next time!