Effect of the cathodic protection on coated steel/artificial sea water system

D.M. SANTÁGATA; C. MORZILLI; C.I. ELSNER; A.R. DI SARLI

CORROSION REVIEWS - (Print)

FREUND PUBLISHING HOUSE LTD

Lugar: Tel Aviv; Año: 1996 vol. 14 p. 135 - 144

0334-6005

In normal corrosion, the current required for the complementary cathodic reaction is supplied by electrons coming from the dissolution of the anodic metallic surface; however, such electrons can also be obtained by an external source (impressed current system). In the latter case, for protecting buried or submerged metallic structures against corrosion, the necessary current is transported from the anode (either active or inert) to the mentioned structure in such a way as to turn it totally cathodic. Taking these concepts into account, the influence of the cathodic protection on the physicochemical behaviour of some carbon steel/organic coating/artificial sea water system, for different type and thicknesses of epoxydic coatings as well as cathodic potential values was investigated. In order to accelerate the tests, several coated samples were scratched in different places. It was conclude that data obtained from both the accelerated electrochemical laboratory tests and the normalized procedures afforded a fairly reasonable performance prediction about the painting scheme-cathodic protection compatibility under specific operation conditions.