Do You Know the Vacuum Die Casting Process?
1. What is the vacuum die casting process?
Vacuum die casting is also known as vacuum assisted high pressure die casting. It is a high pressure die casting process in which a vacuum pump is used to remove air and gases trapped in the mold cavity. Vacuum die casting can be considered as an upgrade to the traditional die casting process. The die casting process remains almost the same with only a few tweaks to create a vacuum in the system. Vacuum die casting is often combined with a cold chamber die casting process. It helps to overcome some difficulties and reduce casting defects in the die casting process.
Vacuum die casting materials have many applications in the automotive industry as well as many other commercial industries. The main advantages of vacuum die casting include higher quality surface finish, improved mechanical properties and overall better finished product stability compared to other more traditional casting methods.
2. What is the vacuum die casting process?
The vacuum die casting process can be done in different ways. It is mainly differentiated based on how the vacuum is created in the system. The two main actions that take place throughout the process are the injection of the melt and the creation of a vacuum. The vacuum die casting process can be controlled in three ways. The injection of molten metal and the generation of vacuum are performed simultaneously. First a vacuum is created in the mold cavity, and then molten metal is injected. Injection and vacuum generation times are controlled by sensors. Therefore, the vacuum die casting process can be done in any of these ways. But here is an overview of the process to give you a better understanding of vacuum die casting.
Molten Metal: The first thing to do before you start using vacuum die casting is to touch the metal. While this may seem like an easy task, it definitely isn't. Metals often need to be melted in a controlled environment for better results.
Slow injection at low pressure: The melt is poured into a cylinder, and with the help of a piston, the melt is driven into the mold cavity. In the case of vacuum die casting, the melt is slowly pushed into the mold cavity at low pressure.
Vacuum creation: Then open the vacuum valve and use the vacuum pump to remove the air in the mold cavity. Once the air is removed and there is sufficient negative pressure in the mold cavity, the vacuum valve closes.
Rapid injection under high pressure: After the vacuum is formed, the melt enters the mold cavity rapidly under high pressure. Due to the vacuum, the melt spreads evenly in the cavity without leaving any holes or voids.
Solidification and removal of castings: Allow the melt to cool and solidify in the mold cavity. The mold is then ejected and the finished product is taken out. After that, the machine will be ready for the next casting operation.