Visualisation of the Galvanic Effects at Welds on Carbon Steel

• Autor(a) principal: Pagotto,Josias F.
• Data de Publicação: 2015
• Outros Autores: Montemor,Maria F., Recio,Francisco J., Motheo,Artur J., Simões,Alda M., Herrasti,Pilar
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532015000400667
• topic: carbon steel; galvanic couple; corrosion; welding

Non-destructive classical techniques, such as electrochemical impedance spectroscopy (EIS) and open circuit potential (OCP) measurement, were complemented with advanced techniques, including the scanning vibrating electrode technique (SVET) and localised electrochemical impedance spectroscopy (LEIS) to examine galvanic effects at welds on carbon steel. The classical techniques indicated that corrosion processes are accelerated in the weld. The advanced techniques revealed admittance values related to more severe corrosion along the weld than in the base metal and higher corrosion currents in the weld. When the weld and base metal are electrically connected, the weld serves as a cathodic protector for the base metal.