PVD multi arc ion plating
1． Introduction and principle of multi arc ion plating
If two or more vacuum arc evaporation sources are used, it is called multi arc ion plating or multi arc plating. It is a kind of vacuum ion coating technology using vacuum arc discharge as evaporation source (evaporation source is solid cathode target, plasma is directly generated from cathode target source, arc target can be arranged in any direction and multiple sources to ensure uniform color on coating). Its arc form is to form cathode arc spot on the surface of cold cathode. When the cathode is heated to high temperature by a large number of high-speed positive ions, the cathode potential drop decreases and the discharge current increases due to the significant hot electron emission. The cathode potential drop only needs to maintain the energy in the cathode region (that is, the product of current and cathode potential drop), which is enough to maintain the temperature required for electron thermal emission.
2． Principle of arc discharge
In the cathode arc discharge, only those tiny areas with the highest temperature, the strongest electric field or the lowest work function emit electrons. Therefore, we can see through the observation window of the machine that the vacuum arc has a circle of flashing bright glow on the cathode surface, which is caused by one or several discontinuities The formation of very small and bright glow spot (called cathode glow spot or cathode spot) is a series of arc processes formed by the arc spot track of a series of rapid processes of extinction, re shift generation and re extinction.
3． Film system and color of multi arc plating
Vacuum multi arc ion plating has been widely used in cutting tools, tableware, glass, ceramics and crystal products. Plastic and all kinds of hardware products. The membrane system includes TiN.ZrN.HfN . TiAIN.TiAINC.TiC . TiNC.CrN And so on. The color films are gun black, black, purple, brown, sapphire blue, rose, bronze, gold, seven colors, etc.