Application of scanning vibrating electrode techniques to study the degradation of coil-coated steel at edges

The Scanning Vibrating Electrode Technique (SVET) has been applied to the study of the degradation of coil-coatings at edges. From the results it is shown that the amount of chromate and its availability in the polymer matrix will be important factors for the initiation of corrosion at edges. It is also shown that the environmental conditions of accelerated corrosion tests play a major role in the propagation of corrosion at the edge of coil-coated steel. Measurements have also been performed on different primers with chrome-free inhibiting pigments. From the results it is shown that SVET is a powerful tool for quick evaluation of the progress of corrosion at the edges for both chromate containing and chrome-free primers.