New Sol-gel Formulations to Increase the Barrier Effect of a Protective Coating Against the Corrosion and Wear of Galvanized Steel

• Autor(a) principal: Kunst,Sandra Raquel
• Data de Publicação: 2015
• Outros Autores: Cardoso,Henrique Ribeiro Piaggio, Beltrami,Lilian Vanessa Rossa, Oliveira,Claúdia Trindade, Menezes,Tiago Lemes, Ferreira,Jane Zoppas, Malfatti,Célia de Fraga
• 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=S1516-14392015000100138
• topic: hybrid film; PEG; corrosion; wear; galvanized steel

This study proposes a new pretreatment method that uses alkoxide precursors with a plasticizing agent; the purpose of this study is to improve the electrochemical and mechanical properties of a galvanized steel surface. Galvanized steel was covered with a hybrid film obtained from a sol that consisted of two alkoxide precursors, 3 - (trimethoxysilylpropyl) methacrylate (TMSM) and tetraethoxysilane (TEOS), with nitrate cerium in a concentration of 0.01 M and a polyethylene glycol (PEG) plasticizer. The hybrid coatings were obtained by dip-coating method with various concentrations of plasticizer (0, 20, 40 and 60 g.L-1). The hybrid films were analyzed by scanning electron microscopy (SEM), profilometry, contact angle measurements, a tribometer with the type-setting ball on the plate and electrochemical tests. The addition of the plasticizer into the hybrid films improves the corrosion resistance behavior compared to the sample without the plasticizer. The addition of 20 g.L-1 of plasticizer showed the best performance in the electrochemical tests. The mechanical behavior results indicated that higher PEG concentrations resulted in films with enhanced durability.