When molten metal is force-pressed highly to form mold […]
When molten metal is force-pressed highly to form mold cavities, this process is called die casting. The process is basically used to form different desired shapes out from hardened metal.
The process started in the early days and was done first using the low pressure injection method. But as time passed by with the technology rising, the use of high end, high pressure techniques like two of the most common squeeze casting and semi-solid casting processes have become more effective than the previous method. Before, only tin and lead were involved in this process, but today even copper, alloys and magnesium can already be used and done with the famous high-pressure method.
Basically, there are four types of dies, namely, single cavity, multiple cavity, unit die, and combinations die. The first type, single cavity, as the name implies is made to produce a component. The second one, the multiple cavity die, is used to create a number of equal or matching parts. The third type which is the unit die is used to produce various types at the same time. And lastly, the combinations die is used to create a number of varying parts for an assembly.
The creation of the die casting products is done under high speed and pressure where the molten metal is injected to the die. With the use of high pressure and speed, smooth and accurate castings can be produced. This pressure exerted on the materials should be maintained until the metal forms and solidifies into the desired shapes. Right after the metal becomes hard, immediately open the die and remove the output product.
Just like any other processes, die casting methods have both advantages and disadvantages. The benefits of die casting include die casting parts have longer service life, good tolerance, and accurate dimensions compared to other castings, the process is economical, the mold can be re-used, it can be done through an automated process and so on. On the other hand, the disadvantages of die casting process appear the initial cost is quite expensive, there is a casting weight preference which is between 30 grams, the casting product should be smaller in size than 24 inches or 600mm, and the process is only limited to highly elastic metals.
As mentioned above, as one of the advantages, the process can indeed be fully automated. With the modern enhancements on the process, there are machines which are fabricated to ensure consistency in quality. The entire automation process covers the whole die casting process, including lubrication of metals to pouring metals to the chamber.