The steels that typically require anti-corrosion coatin […]
The steels that typically require anti-corrosion coating are hot dip galvanized steel and thermal spray zinc steel. Zinc is a kind of active metal. The purpose of zinc coating is to provide cathodic protection and rust protection to steel. This function is the same as that of zinc-rich primer.
The surface coated with a zinc metal coating has the following differences compared to bare steel:
1. Whether it is hot-dip galvanized steel or hot-sprayed zinc steel, the surface is usually relatively smooth, and it is no longer possible to perform jet cleaning like bare steel to achieve a certain roughness requirement;
2. The active zinc surface will produce zinc salt after a period of exposure;
3, active zinc easily with some oil paints (such as alkyd, phenolic, etc.) fatty acids or other active ingredients in paint saponification;
4. Since the zinc metal coating has been provided for protection, the protective paint coating system for the post-coating can be thinned accordingly.