Why Choose Vacuum Die Casting?

Ⅰ. What is vacuum die casting?

In vacuum die casting, a vacuum is used to draw the molten metal into the mold cavity, different from semi solid metal casting. Both techniques are used to produce high-quality castings with good surface finishes, high dimensional accuracy, and reduced porosity compared to other casting methods. They are commonly used in the production of small, intricate parts where high precision and tight tolerances are required.

Also as a China stainless steel casting company, we acknowledge that vacuum die casting can be considered as an upgraded version of traditional pressure die casting. It is a high-pressure die-casting that removes the air in the mold cavity with the assistance of a vacuum pump. This is why the process is also known as vacuum-assisted high-pressure die casting. Vacuum die casting is mainly used to reduce some casting defects caused by air entrainment in parts. Vacuum die casting helps manufacturers overcome many of the problems associated with traditional die casting. So why do we choose vacuum to die casting? 

Ⅱ. Reasons for choosing vacuum die casting

Different from other types of castings like silica sol casting, vacuum die casting has the following features:

1. Reduce porosity: porosity is a common problem in the die-casting process. It is almost impossible to completely eliminate porosity with traditional die-casting technology. But with vacuum die casting, you can expect to produce parts with virtually no porosity.

2. No surface defects: Die casting that is not fully ventilated will result in trapped air in the cavity. It causes surface defects such as blisters and pores. You may not be able to fix these defects and have no choice but to discard the part.

3. Better mechanical properties: Vacuum die casting can produce parts with better mechanical properties. The metal is denser due to the reduced porosity. This significantly increases mechanical strength and enhances several other properties.

4. Thinner Walls: You don't have to worry about providing thinner walls in a vacuum assist system. The molten metal manages to reach the narrow grooves due to the negative pressure created by the vacuum. Therefore, vacuum die casting ignores the chance of leakage.

5. Increased production capacity: Theoretically speaking, vacuum die casting takes almost the same time as any conventional die casting method. However, vacuum casting significantly reduces part defects and provides a better surface finish. Therefore, vacuum die casting does not require any post-processing operations. This will save the manufacturer time and money.

6. Reduce waste: Without proper quality control, conventional die casting can produce many defective parts. Some defects may be dealt with, while at other times you will have to reject parts. Vacuum die-casting reduces possible die-casting defects and reduces waste during production.

7. Heat treatment and welding are available: usually die castings are not suitable for heat treatment. Due to the presence of pores inside the die casting, high temperatures can form surface bubbles. Vacuum die casting ignores this problem and allows heat treatment of die castings of certain metal alloys. The parts produced are also better weldable.

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