Some Understandings on Processing Characteristics of PVD Coating

1. PVD coating processing increases the mold manufacturing cost, why does it reduce the production cost?

Coating increases the cost of mold manufacturing, accounting for about 10% of the total mold cost. However, if the total cost of producing each product is calculated, because of the effectiveness of the coating, the service life of the mold is extended several times, and the demoulding is easy, the downtime for mold maintenance is reduced, and the production volume is doubled or the production time is shortened, then the production cost of each product must be reduced a lot.

2. The hardness of PVD coating is very high, so the hardness of base steel does not need to be improved?

PVD coating is only a thin layer (1~10 μ m) The cermet coating is mainly used to improve the surface hardness and wear resistance, mainly for parallel friction, so the hardness of the substrate is very important. The temperature of stamping die is required to be above 55 ℃, and the temperature of plastic die is required to be above 30 ℃. If the hardness of the stamping die is not higher than HRc60, the matrix will be like "tofu" and plastic deformation will occur immediately. Therefore, the hardness of the substrate will not be reduced due to the use of the coating.

3. Can any material be PVD coated?

PVD coating is processed under high vacuum and low temperature (about 200 ℃ or 400 ℃). If the material melts or becomes soft at this temperature (such as zinc), PVD coating cannot be made. Such problems do not exist in ordinary die steel and hard alloy.

4. Is the coating as thick as possible?

The thicker the coating is, of course, the longer the wear resistance time is. However, based on the inverse relationship between the PVD coating thickness and the adhesion of the substrate, the PVD coating cannot be too thick. Verified, 1-4 μ M is the appropriate coating thickness.

5. Is the principle of PVD coating the same as that of chrome plating and nickel plating?

Chromium and nickel plating are coatings made by common electrolysis principle, but PVD coatings are deposited by plasma technology. PVD coating can be 1~10 μ M, with control accuracy of 0.5 μ M, but electroplating process can not reach this range. The hardness of chromium plating is about Hv1000, while the hardness of PVD coating can reach above Hv4000.