Criterion for Cathodic Protection of 25CD4/Inconel 182 System

Auteurs :  ALLOU Djilali, CHENITTI Billal
Année : 2018
Domaine : Sciences des matériaux
Type : Communication
Conférence: The 3 rd International Conference on Engineering Technology and Applied Sciences
Résumé en PDF :  (résumé en pdf)
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Mots clés : cathodic protection, 25CD4, Inconel 182, overlay

Résumé : 

In this work ,the cathodic protection criterion of a system consisting of a galvanic coupling between a low alloy steel 25CD4 / Inconel 182 austenitic stainless-steel filler metal which were prepared by Shield Metal Arc Welding (SMAW) process, have been studied. he microstructures of the dissimilar metal joints have been investigated by optical microscopy, scanning electron microscopy, and X-ray diffraction analysis at the interface showed a gradient variation of Fe, Cr and Ni between boundaries of fusion and type II, where the highest hardness value was recorded.Potentiodynamic polarization tests of different regions of the welded joints evaluated in a marine environment (5% NaCl) at room temperature, exhibit a high corrosion resistance of both weld metals. Cronopotentiometry was used to determine the system protection criterion using corrosion potential of the least noble material. It was found that the cathodic protection criterion for the assembly is based on the criterion of the least noble material.