In the past ten years, the development of vacuum ion plating technology is the fastest, and it has become one of the most advanced surface treatment methods in contemporary times.
PVD (Physical Vapor Deposition) means "physical vapor deposition" in Chinese. It refers to a thin film preparation technology that uses a physical method to deposit materials on the workpiece to be plated under vacuum conditions. PVD technology is mainly divided into three categories: vacuum evaporation coating, vacuum sputtering coating and vacuum ion coating.
The similarity between PVD coating and traditional electroless plating is that both belong to the category of surface treatment, and both cover the surface of one material on the other material in a certain way. The difference between the two is: PVD coating has greater bonding force with the surface of the workpiece, the hardness of the coating is higher, wear resistance and corrosion resistance are better, and the performance of the coating is more stable; PVD coating can be plated The types of coatings are more extensive, and the colors of the coatings that can be plated are more and more beautiful; PVD coating will not produce toxic or polluting substances.
However, at this stage, PVD coating cannot replace chemical electroplating. In addition to the direct PVD coating on the surface of stainless steel materials, it is necessary to apply PVD coating on workpieces of many other materials (such as zinc alloy, copper, iron, etc.). They need to be electrolessly plated with Cr (chromium).
PVD coating is mainly applied to some relatively high-end hardware products. For those hardware products with lower prices, it is usually only subjected to chemical plating instead of PVD coating.
Vacuum evaporation coating, vacuum sputtering coating, vacuum ion coating The comparison of the three coating methods is as follows:
| Compare items | Vacuum evaporation coating | Vacuum sputtering coating | Vacuum ion plating | |
| Pressure (×133Pa) | 10E-5~10E-6 | 0.15~0.02 | 0.02~0.005 | |
| Particle energy | neutral | 0.1~1eV | 1~10eV | 0.1~1eV |
| ion | － | － | Hundreds to thousands | |
| Precipitation rate (μm/min) | 0.1~70 | 0.01~0.5 | 0.1~50 | |
| Diffraction | difference | better | it is good | |
| Adhesion | not too good | better | well | |
| Film compactness | Low density | high density | high density | |
| Pores in the film | More at low temperature | less | less | |
| Internal stress | Tensile stress | Compressive stress | Compressive stress | |
