Characteristics of paint coating protection

The preparation of metal surface, especially the performance of inorganic film on metal surface plays an important role in the protective performance of paint. Similarly, the corrosion resistance of paint coating is different with the performance of inorganic film. Inorganic film can greatly improve the protective effect of paint coating. If the film-forming material has saponification effect, then it can be used as the primer, and the inorganic membrane effect will be more prominent. The adhesion of the primer was improved by inorganic film.

Before coating, the surface to be coated must be cleaned and oxidized. After oxidation, the parts should be heated at 100 ~ 105 ℃ to remove the residual moisture in the gap. The primer should be applied within 48 ~ 72h after oxidation, otherwise the adsorption property of oxide film will decrease, which will make the adhesion between coating and film worse.


The paint type should be selected according to the working environment of the parts and whether it is possible to use heat curing. In order to achieve high quality coating, high temperature curing is ideal.


We generally divide the use environment of parts into three types:

① Atmospheric corrosion environment;

② Periodic heating environment;

③ The service temperature is lower than 80 ℃ and there is no corrosive gas environment.


With the development of lightweight automobile, magnesium alloy tire bead is on the way to industrial application. Because of the harsh environment of automobile tire bead, it constitutes a serious corrosion condition to the tire bead. The corrosion protection of magnesium alloy tire bead can be used as a typical example of magnesium alloy combined with anodizing and paint in severe corrosion environment.