Detecting pitting corrosion and its severity using wavelet entropy in electrochemical noise measurement

Authors

Abstract:

Entropy as a measure of uncertainty was used to represent the results of the wavelet technique in electrochemical noise analysis. The experimental signals were obtained by recording the electrochemical potential and current noise of 7075 aluminum alloy in 3.5% NaCl solution. The electrochemical potential and current noise were decomposed into 16 levels using Daubechies wavelets. Wavelet output etropy was calculated using a kernel density estimator and the Shanon equation. It was demonstrated that low frequency scales had the highest entropy magnitude for passivation of aluminum surfaces in all experiments. The entropy contribution to high frequency scales decreased with the appearance of pits and as the pits increased and enlarged on the electrode surfaces (detected by scanning electron microscopy). The amount of reduction in entropy magnitude was attributed to the severity of pitting corrosion. It appears that a wavelet-entropy plot is a promising method to differentiate between different types and the severity of corrosion.

Upgrade to premium to download articles

Sign up to access the full text

Already have an account?login

similar resources

detecting pitting corrosion and its severity using wavelet entropy in electrochemical noise measurement

entropy as a measure of uncertainty was used to represent the results of the wavelet technique in electrochemical noise analysis. the experimental signals were obtained by recording the electrochemical potential and current noise of 7075 aluminum alloy in 3.5% nacl solution. the electrochemical potential and current noise were decomposed into 16 levels using daubechies wavelets. wavelet output ...

full text

Corrosion Evaluation Using a New Electrochemical Impedance Measurement Technique

In this paper, a new approach to the computation of electrochemical impedance spectroscopy (EIS) is presented where the EIS system is represented by a convolutional model, and thus the impedance of the EIS system is computed using robust deconvolution algorithms. Very promising results are obtained .

full text

Electrochemical Noise Analysis of Anaerobic (Bacterial) Corrosion of Steel

Corrosion of structural steel in an SRB containing environment for as long as 9 months, is studied using the Electrochemical Noise Analysis technique. The results show that the activity of the system, which was very low initially, started to increase after 6 months exposure to the environment. The power spectral density curves of the Electrochemical Potential Noise of the system, using the maxi...

full text

Electrochemical Studies of Pitting Corrosion of Cu-fe Alloy in Sodium Chloride Solutions

The electrochemical studies of pitting corrosion of CuFe alloy (70% Cu30%Fe) were carried out in sodium chloride solutions. The techniques of measurements were: open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy. The effect of different concentrations of the inorganic additives (WO4 , PO4 , NO2 , B4O7 , CrO4 ) on the pitting corrosion of the alloy in...

full text

ELECTROCHEMICAL NOISE ANALYSIS OF 70-30 BRASS DURING STRESS CORROSION CRACKING TEST IN MATTSON S SOLUTION

An investigation of the electrochemical noise generation during Stress Corrosion Cracking (SCC) of 70-30 Brass in Mattson's solution was conducted. The fluctuations of potential and current were monitored. The relationship between potential and current fluctuations has been evaluated in time domain and the obtained data has been analyzed in the frequency domain using Power Spectral Density (PSD...

full text

My Resources

Save resource for easier access later

Save to my library Already added to my library

{@ msg_add @}


Journal title

volume 2  issue 1

pages  116- 122

publication date 2014-06-01

By following a journal you will be notified via email when a new issue of this journal is published.

Hosted on Doprax cloud platform doprax.com

copyright © 2015-2023