The uneven corrosion of deep drawn coil-coatings investigated by EIS

abstract

The corrosion distribution along a coil-coating sample formed by deep-drawing is reported. The formed rectangular cup was divided in five different regions and their impedance response investigated independently. The response of each region was compared with the overall sample response and the morphology of degradation was studied by scanning electron microscopy. Severe attack was observed in the most strained regions (corners and edges). Micro-defects in the shape of pinholes and cracks developed as a consequence of the forming process, apparently nucleating in the vicinity of the inorganic particles present in the paint. Immersion increased the size and number of defects. The overall impedance was reconstructed from the impedance measured in the local regions by two methods: (a) calculation using the local experimental data and (b) simulation using an equivalent electrical circuit with the values taken from the fitting of the local experimental data. (C) 2010 Elsevier Ltd. All rights reserved.

keywords

PAINTED STEEL SHEETS; MECHANICAL DEFORMATION; GALVANIZED STEEL; FORMABILITY; METALS

subject category

Electrochemistry

authors

Bastos, AC; Ferreira, MGS; Simoes, AMP

our authors

Share this project:

Related Publications

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".