ELECTROCHEMICAL NOIS E SIGNAL PROCESSING USING R/S ANALYSIS AND FRACTIONAL FOURIER TRANSFORM

The corrosion processes of stainless steel under different solutions were examined using Electrochemical Noise (ECN). Using Rescaled Range analysis, we demonstrated that ECN signals produced by corrosion processes have non-stationary and self-similar properties. The comparison and analysis of ECN signals in both time and frequency domain showed that the conventional methods failed to give out the differences of the ECN signals obtained under different solutions. Therefore, we introduced fractional Fourier transform (FrFT) to process ECN signals, which is a powerful tool for the time-frequency analysis of self similar signals that can better describe the corrosion behaviours of the electrode in different solutions.