Corrosion Performance of Stainless Steel and Nickel Alloys in Aqueous Sodium Hydroxide as Revealed from Cyclic Voltammetry and Potentiodynamic Anodic Polarization

Abstract

The electrochemical behavior of nickel, Inconel 600, Incoloy 800 and 316 stainless steel electrodes in different concentration of NaOH solution was investigated using the cyclic voltammetry technique (CV). All the curves in the anodic branch of the CV are characterized by anodic dissolution peak (A), passive region (B), anodic dissolution peak (C) before oxygen evolution. In the case of the cathodic branch of CV there is one reduction peak (D) in case of Ni electrode but there are two reduction peaks (D and E) in case of the three alloys used. All these peaks are explicated. The effect of chloride ion as a pitting agent on the cyclic voltammetry and the potentiodynamic anodic polarization of Ni ,Inconel 600, Incoloy 800 and 316 SS electrodes in NaOH solution was investigated. As the concentrations of the chloride ions increase the change of the amount of the anodic charge Δq a increases and the values of the pitting corrosion potential are shifted to the more negative direction indicating the breakdown of passivity and the imitation of the pitting corrosion. At one and the same Cl -ion concentration, the resistance to the pitting attack decreases in the following order: 316SS > Inconel 600 > Incoloy 800> 316 SS. This order depends on the chemical composition of these alloys.

An Investigation into the Corrosion Rates of Inconel 600™ in Different Corrosive Solutions

“…The analyzed area showed an inclusion of about 29.7 µm 2 . This was also confirmed by the studies done by Abdallah et al [6][7][8] that showed the extent of pitting corrosion of the Inconel 600™ alloy when exposed to various acids and bases and that the grain boundary precipitates would correspond to (Cr -Fe) 23 C 6 and TiN.…”

“…5 The corrosion rates reported varied between 0.033 and 0.8344 mm yr -1 and were obtained in solutions that varied between 0.01 M to 10.00 M, respectively. Extensive studies in using Inconel 600™ in nitric acid and caustic soda applications were performed by Abdallah et al [6][7][8] They made use of cyclic voltammetry to investigate the formation of the passivation film and compared it to other alloys such as Incoloy 800 and 316 stainless steel.…”

Experimental Investigation of the Hydroxy Gas Generation as a Clean Energy Source for Spark Ignition Engine Operation Using Different Electrolytes

“…The chemical reactions occurring in the electrolyzer have slightly darkened the electrolyte. The use of (316 SS) electrodes would probably have prevented this (Abdallah et al, 2017).…”

Performance of unprecedented synthesized biosurfactants as green inhibitors for the corrosion of mild steel-37-2 in neutral solutions: a mechanistic approach

“…Most inhibitors are organic compounds containing heteroatoms (N, O, S), unsaturated bonds and plane conjugated systems [2][3][4][5][6][7][8][9]. They are adsorbed on the steel surface and block it, thus preventing corrosion [9].…”