Influence of Molybdenum and Tungsten on the Formation of Zirconium Oxide Coatings on a Steel Base

In this paper, we have developed conditions for the deposition of zirconium oxide coatings from solutions containing hexafluorozirconic acid as well as tungsten and molybdenum salts on a steel base. Based on electrochemical studies, it was shown that the addition of tungsten and molybdenum salts to the solution to deposit zirconium oxide coatings led to the inhibition of the anodic process of iron ionization. It was shown that the optimal conditions for the deposition of oxide-zirconium coatings on the surface of steel samples from a solution of 0.2 g/L Zr (IV) + 0.15 g/L W (VI) + 0.1 g/L Mo (VI) were a deposition temperature of 30 degrees C and time of 10 min. The thickness of the oxide-zirconium coatings formed under these conditions was 64.72 nm, the adhesion value was 3.17 MPa/s, and the corrosion resistance was 26 s according to Akimov's drop method. The depth of corrosive penetration, determined in the salt fog chamber, did not exceed 2 mm after 240 h of testing, meeting the requirements for adhesive layers under the paintwork.

Automated summary

This study demonstrates that the addition of tungsten and molybdenum salts to the solution can help deposit zirconium oxide coatings on steel with improved corrosion resistance. The optimal conditions for coating deposition were found to be Zr(IV) 0.2 g/L + W(VI) 0.15 g/L + Mo(VI) 0.1 g/L, deposition temperature of 30 degrees C, and time of 10 min. The coatings formed under these conditions showed a thickness of 64.72 nm, adhesion value of 3.17 MPa/s, and corrosion resistance of 26 s.