How to degas the vacuum coating machine?
The vacuum state is the environment that supports the operation of the vacuum coating machine, especially the equipment that requires high vacuum. Usually we need to achieve high vacuum. The role of the air extraction system is indispensable, but in addition to the air extraction system, the vacuum coating equipment In the process of operation, another point is the outgassing of the workpiece.
There are a lot of gas, moisture, etc. inside some workpieces. These substances will be discharged into the vacuum chamber when the equipment is heated, reducing the vacuum degree. What's more, some gases have toxic components that directly damage the vacuum chamber. The internal mechanical structure causes the equipment to fail to operate normally.
In addition, during the coating process, the gas in the workpiece is heated and expanded, which will easily cause the coated film to crack. Of course, the probability of this situation depends on the physical properties of the workpiece itself. The probability of easy expansion like plastic is relatively high. The probability of hard materials such as metal is relatively low, but it cannot be ignored. Therefore, the degassing of the workpiece is very necessary.
The degassing method we usually use for the workpiece is baking. The gas and moisture in the workpiece are discharged by heating. Before coating, the workpiece is heated while the gas is pumped. When the moisture and gas in the workpiece are released due to heating, the The gas in the vacuum chamber is pumped out by the vacuum pump.
Different degassing measures are adopted for different workpieces to effectively control the emission of gas and moisture inside the workpiece and improve the stability and uniformity of the coating.