Criterion for cathodic protection of 25CD4/Inconel 182 system

Type : Publication
Auteur(s) :  D. ALLOU, D. Miroud, M. Ouadah, B. Cheniti, S. Bouyegh
Année :  2020
Domaine : Sciences et génie des matériaux
Revue : Applied Surface Science
Résumé en PDF :  (résumé en pdf)
Fulltext en PDF :  (.pdf)
Mots clés :  cathodic protection, 25CD4, Inconel 182, overlay, Cronopotentiometry.

Résumé : 

This study aims to investigate the cathodic protection criterion of a galvanic system of low alloy steel 25CD4substrate /Inconel 182 austenitic stainless-steel ?ller metal couple obtained using Shield Metal Arc Welding(SMAW) process. The microstructure investigation revealed the presence of Type II boundary along the steelsubstrate/Inconel interface where high carbon content and high hardness were recorded. The electrochemicaltests evaluated in marine environment (3.5% NaCl) at room temperature revealed that the corrosion potential(E) of the interface was between the steels substrate and the Inconel 182 ?ller metal ones, On the other hand,the current density (Icorr) and corrosion rate were slightly higher in the overlaid area. In order to determine thesystem protection criterion, chronopotentiometry method was introduced. It was found that the cathodic protectioncriterion for the assembly is based on the criterion of the least noble materialwhich is the steel substrate.corr