Electrochemical noise analysis of duplex stainless steel 2101 exposed to different corrosive solutions

Abstract

The corrosion behaviour of duplex stainless steel 2101 exposed to 0.1 wt-%NaOH, 5.0 wt-%H 2 SO 4 and 6.0 wt-%FeCl 3 solutions was investigated with an electrochemical noise technique. The time records revealed salient features of the steel in the three solutions, and the corresponding corrosion morphologies were shown. The slopes of the power spectral density plots of current and potential noises were associated with the nature of corrosion attack. The corrosion rates in the three media were reflected by the noise resistance, presenting good correlation with the results from linear polarisation and electrochemical impedance spectroscopy. research has been dedicated to the studies of the DSS. carbon steel, aluminium, iron and copper, and limited ported data have been obtained on stainless steel, mild steel, terials and environments. of ma dying the nature of corrosion processes on a wide range vestigators have determined the reliability of ENM for stu-ises can be obtained. During the past few years, many in-the power spectral density (PSD) of potential and current no-

Electrochemical Noise Measurements of Advanced High-Strength Steels in Different Solutions

“…Similarly, the roll-off slope becomes more negative with the addition of Cl − ions. A gradual decrease of roll-off slope with time in Cl − containing solution is observed, and many small pit nuclei are generated [87]. The slopes of the power spectral density plots of current and potential noises were associated with the nature of corrosion attack on duplex stainless steel 2101 [88].…”

AM60-AlN Nanocomposite and AM60 Alloy Corrosion Activity in Simulated Marine-Coastal Ambience

“…The data analysis enabled to calculate the electrochemical noise resistance R n values [49], considered as an equivalent to the values of polarization resistance (R p ) [55][56][57][58][59][60][61]: The amplitudes of the EN oscillations are considered usually as an indicator for the initiation and propagation of the localized pitting corrosion at the early stages, changes in the morphology and composition of the layers formed on the surface, influenced by the presence of chloride ions [54], among others. A larger amplitude of the electrochemical current noise can be observed in the case of the AM60-AlN composite (Figure 5a), ascribed to more accelerated corrosion kinetics, than that of AM60-alloy (Figure 5b).…”

“…The data analysis enabled to calculate the electrochemical noise resistance R n values [49], considered as an equivalent to the values of polarization resistance (R p ) [55][56][57][58][59][60][61]:…”

“…Figure presents the fluctuations in the free corrosion current density (at OCP) at 30 days of immersion in SME model solution of the nanocomposite AM60-AlN (Figure5a) and AM60 alloy (Figure5b). The corrosion current signals at the metal surface, being in contact with the solution, were considered as an electrochemical noise (EN), because they are typically of low-level amplitude[49], caused by the spontaneous natural variations in the time of the electrochemical process kinetics[55][56][57][58][59][60][61].…”