Aluminum die casting is a metal forming process that can create complex aluminum parts. Aluminum alloy ingots are heated to very high temperatures until they are completely melted.
Liquid aluminum is injected under high pressure into the cavity of a steel mold (also known as a mould) – you can see an example of a mold for an automotive part above. The mold consists of two halves, and after the molten aluminum solidifies, they are separated to reveal the cast aluminum part.
The resulting aluminum products are precisely shaped, have a smooth surface, and typically require minimal or no machining operations. Given the use of steel molds, the process can be repeated many times before the same mold fails, making aluminum die casting ideal for high-volume production of aluminum parts.
Advantages of Aluminum Die Castings
Aluminum die casting has several advantages over other metal forming processes that may make it a suitable choice for manufacturing aluminum parts.
One of the most notable is the ability to produce very complex shapes that neither extrusion nor machining can effectively create. A perfect example is the production of complex automotive components such as transmissions and engine blocks. No other process can consistently achieve the complexity and tight tolerances these products require.
Other advantages include the ability to have textured or smooth surfaces and the ability to accommodate parts large and small.
The most common die-cast aluminum alloy
Some of the most commonly used aluminum alloys for die casting are A380, 383, B390, A413, A360 and CC401. When selecting the appropriate alloy, the first consideration is your intended application.
For example, A360 has excellent corrosion resistance, pressure resistance and very good flow when molten. B390 has excellent wear resistance and high hardness, while having the lowest ductility of any cast alloy, which is why it is used in applications such as automotive engine blocks. Alloy A380 is the perfect jack of all trades, offering a good combination of casting and product properties, and is the most commonly specified alloy for casting a wide variety of products.
