Evaluation of corrosion resistance of powder coatings after various surface chemical pre-treatment

The surface treatment by a powder coating is one of the progressive technologies. Such coatings are resistant to corrosion and mechanical wearing. The quality of surface protection is affected primarily by a layer pre-treatment, the type of surface tretment, the system selection and the method and quality of application. Taking into account all the surface pre-tretment methods, the chemical pre-modification is a leading method. One of the methods is pre-treatment using a conversion coating which was developed on the nanotechnology basis - BONDRITE NT. That non-phosphate chemical pre-treatment is utilized at a surrounding temperature. It creates nano-ceramic protective layer on steel, zinc and aluminium surfaces, and as the result the coating has a significant adhesion. In the paper, the possibilities for the improvement of corrosion resistance of powder coatings using the subject conversion coating are presented at the current pasivation of respective surface.