Fabrication of superhydrophobic coating on PEO treated zirconium samples and its corrosion resistance

The present work reports the fabrication of superhydrophobic oxide layer on commercially pure zirconium samples. A two-step process, plasma electrolytic oxidation process (PEO) followed by stearic acid treatment was employed to fabricate the superhydrophobic layer on Zr substrate. The PEO process was carried out in sodium aluminate electrolyte for 6 min. After that, the PEO coated specimens were immersed in the 0.01 M ethanolic solution of stearic acid. The oxide layer developed by the PEO process was modified using stearic acid by simple immersion technique. The effects of hydrophobic treatment time on the contact angle (CA) values of the samples were investigated. The contact angle measurement reveals a tremendous increase in the CA of the stearic acid solution treated specimens. The corrosion analysis by potentiodynamic polarization test reveals that the protection efficiency of the coating has been significantly improved by the hydrophobic treatment and the lowest corrosion current (icorr) value was obtained for the specimen, treated with stearic acid for 5 h and, that is 2 orders of magnitude lesser than the base coating. (C) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International conference on Materials and Manufacturing Methods.