Superhydrophobic Surfaces on 5052 Aluminum Alloy Obtained from LDH Film Modified with Stearic Acid for Enhanced Corrosion Protection

• Autor(a) principal: Malta,Maria Isabel Collasius
• Data de Publicação: 2019
• Outros Autores: Vieira,Magda Rosângela Santos, Silva,Rafael Gleymir Casanova da, Silva,Leonardo Mendonça Carneiro da, Araújo,Edval Gonçalves de, Maciel,Sara Horácio De Oliveira, Urtiga Filho,Severino Leopoldino
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392019000600236
• topic: Superhydrophobic Surface; Micro/nanostructured Surface; LDH film; Aluminum alloy 5052; Corrosion

This paper aimed to develop and characterize superhydrophobic surfaces with anticorrosive properties obtained by the chemical modification of the 5052 aluminum alloy with variation of acid etching time, formation of lamellar double hydroxides (LDH) film and immersion in stearic acid. The specimens were etched in HCl (2M) at 5, 10 and 30 min. The aluminum plates were treated with aqueous solution of zinc nitrate (0.1 M) in the presence of ammonia and then immersed in a stearic acid and ethanol solution (1% w/w) to reduce surface energy. Contact angles (CA) were determined. Surface morphology and composition were analyzed by scanning electron microscopy (SEM) and X-ray energy dispersion spectroscopy (EDS), respectively. Linear polarization tests were performed to analyze corrosion resistance. The optimal superhydrophobic performance was obtained with a contact angle of 154º for 30 min of acid etching. This condition also showed higher corrosion resistance, obtaining higher values of Ecorr and lower values of corrosion current density.