Nowadays, there are two main ways to make the coating industry, one is chemical meteorological deposition, that is chemical coating (CVD), and the other is physical meteorological deposition, that is vacuum coating (PVD).

Chemical coating is a process of introducing a gaseous reaction agent or other gases needed for the liquid reaction into the reaction chamber, and a chemical reaction occurs on the substrate surface to form a thin film. In the process of chemical film, it is easy to produce solution pollution, if the coating surface impurities, the effect of plating is not good.

The reaction temperature required by chemical coating is very high, generally controlled at about 1000℃, but many matrix materials can not withstand this high temperature, even if the carbide alloy, although can withstand high temperature, but in the chemical coating environment because of high temperature will also cause coarse grain, cause brittle phase, the performance deterioration.If tin is plated on a hard alloy, the carbon diffused from the crystal will react with the solution to form a decarbonization layer, which has poor toughness and low bending strength, resulting in shortening the service life of the tool.

Vacuum coating machine solves a series of problems caused by chemical coating very well. Vacuum coating is a process of using low voltage and high current arc discharge technology to evaporate the target material and make the evaporated material and gas ionized. Accelerating the electric field makes the evaporated material and reaction products deposited on the workpiece.

All coating materials are deposited on the surface of the workpiece through plasma in a vacuum environment, solving the problem of solution pollution in the chemical coating, which will not produce toxic or polluting substances, and the coating layer has higher hardness, good wear resistance and corrosion, and more stable performance.The temperature of vacuum coating process can be controlled below 150℃ ~500℃, suitable for a variety of matrix materials, can prepare colorful film layer, plating carbide tool can increase its life by 2~10 times.

It can be seen that vacuum coating is the inevitable trend of the development of coating industry, its application has caused the manufacturing industry of the world, environmental pollution, in line with the development direction of modern green manufacturing, from the 20s 50s, chemical coating was gradually replaced by vacuum coating.