Comparative electrochemical studies of zinc chromate and zinc phosphate as corrosion inhibitors for zinc |
| |
Authors: | A.C. Bastos, M.G.S. Ferreira,A.M. Sim es |
| |
Affiliation: | aChemical Engineering Department, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal bDepartamento de Engenharia de Cerâmica e do Vidro, Universidade de Aveiro, Aveiro, Portugal |
| |
Abstract: | The anticorrosive performance of two inhibitive pigments, zinc chromate and zinc phosphate, was compared using electrochemical impedance spectroscopy (EIS) and the scanning vibrating electrode technique (SVET) in pigment extracts in 0.1 M NaCl. It was observed that zinc was protected from corrosion in both extracts. In tests using hot dip galvanised steel painted with an epoxy primer incorporating the pigments, the SVET detected the anodic and cathodic distribution along the scribes, although no significant differences were observed among the various primers. On the contrary, EIS was able to distinguish processes occurring on the metal surface exposed by the scribe in different samples. For primers with anticorrosive pigment, a time constant at high frequencies was attributed to a layer of protective nature, probably formed by metal ions from the substrate and inhibitive ions leached from the anticorrosive pigments. |
| |
Keywords: | Anticorrosive pigments Corrosion EIS SVET Zinc Phosphate Chromate |
本文献已被 ScienceDirect 等数据库收录! |
|