Post-galvanizing
Although galvanized steel’s appearance is increasingly popular, especially for indoor residential applications, this steel is often painted. Today, the techniques used to paint galvanized steel allow for optimal results
Certain conditions must be met when painting galvanized steel. They mainly apply to the state of the surface to be painted and the type of paint to use.
Painting galvanized steel; why?
First of all, for aesthetic reasons. The paint may also have been recommended by the architect in order to identify a project, due to the hostile nature of the environment in which the steel will be used, to repair an already galvanized part, or to increase the product’s life. The post-galvanizing painting process is called a "duplex system".
The advantages are clear:
- • Paint is additional protection for galvanized steel;
- • Galvanized surfaces provide better protection against corrosion;
- • Galvanizing prevents or minimizes paint flaking;
- • The paint-galvanizing tandem guarantees longer surface protection;
- • 1.5 to 2.5 times individual duration.
The "passivation cycle" represents the steel aging process, as presented in the illustration below:
When do you paint galvanized steel?
Galvanized steel can be painted at any step during the steel’s aging process, while however observing certain procedures:
- • Immediately after the galvanizing treatment;
- • When the galvanized steel is at 50% of its life;
- • When the thickness of the galvanized film is ≤1mils.