Double Step Electrochemical Process for the Deposition of Superhydrophobic Coatings for Enhanced Corrosion Resistance

A superhydrophobic coating with high transparency and ultrahigh adhesive force is prepared for application on the glass covers of solar cells, which also exhibits excellent thermal stability and strong acid–base corrosion resistance.

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Development of Superhydrophobic Coatings on AA 7075 by Surface Modification Using Fatty Acids

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.833.69 ◽

2020 ◽

Vol 833 ◽

pp. 69-73

Author(s):

Saikiran Amruthaluru ◽

Siva Kumar Mamidi ◽

Arun Mohan Nair ◽

Hariprasad Sampatirao ◽

Rameshbabu Nagumothu

Keyword(s):

Fatty Acids ◽

Contact Angle ◽

Corrosion Resistance ◽

Surface Morphology ◽

Stearic Acid ◽

Myristic Acid ◽

Superhydrophobic Coatings ◽

Naoh Solution ◽

Aa 7075 ◽

Passivation Time

The present work is aimed at developing superhydrophobic coatings on AA 7075 using two different fatty acids namely Stearic acid and Myristic acid. The coating was developed by initially etching the substrate in 1 M NaOH solution at a temperature of 70 °C for 10 hours, followed by passivating in 0.01 M ethanolic stearic acid and 0.01 M ethanolic myristic acid for different durations of passivation time. The coated samples were further investigated for their surface morphology, wettability and corrosion resistance. The contact angle and surface morphology of the developed coatings were assessed by contact angle goniometer and scanning electron microscopy (SEM) respectively. The corrosion behavior of the coatings was studied in 3.5 Wt. % aqueous NaCl solution by potentiodynamic polarization test (PDP). Passivation using fatty acids resulted in alteration of the surface morphology, which resulted in the increase of the contact angle exhibiting superhydrophobic nature, which also enhanced the corrosion resistance of the alloy.

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Corrosion Protection of Aluminum-Matrix Composites

MRS Proceedings ◽

10.1557/proc-390-129 ◽

1995 ◽

Vol 390 ◽

Author(s):

Jiangyuan Hou ◽

D. D. L. Chung

Keyword(s):

Thermal Conductivity ◽

Corrosion Resistance ◽

Surface Treatment ◽

Aluminum Matrix ◽

Electrochemical Process ◽

Aluminum Matrix Composites ◽

Matrix Composites ◽

Acid Electrolyte ◽

Effective Surface ◽

Aluminum Anodizing

ABSTRACTAluminum-matrix composites are attractive in their combination of low CTE and high thermal conductivity. Anodizing is an effective surface treatment for improving the corrosion resistance of aluminum-matrix composites. ForSiC filled aluminum, anodizing was performed successfully in an acid electrolyte, as usual. However, for AIN filled aluminum, anodizing needed to be performed in an alkaline (NaOH) electrolyte instead of an acid electrolyte, because NaOH reduced the reaction between AIN and water, whereas an acid enhanced this reaction. The concentration of NaOH in the electrolyte was critical; too high a concentration of NaOH caused the dissolution of the anodizing product (A12O3) by the NaOH, whereas too low a concentration of NaOH did not provide enough ions for the electrochemical process.

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