Multifractal Hurst Analysis for Identification of Corrosion Type in AISI 304 Stainless Steel

Fractal analysis methods are able to characterize complex time-series and images. In electrochemical corrosion, fractal parameters (fractal dimension, scaling exponent, correlation factors, etc.) have been correlated to the corrosion mechanism, the surface roughness and long-term behavior. In this work, a two-dimensional re-scaled Hurst analysis method has been utilized for determining the scaling Hurst exponent resulting from the electrochemical corrosion of AISI 304 stainless steel (SS) exposed to FeCl 3 and NaOH solutions. It is found that the AISI 304 SS exposed to FeCl 3 a NaCl solutions exhibits positive correlations and multifractal properties. In order to quantify the complexity of the corroded surfaces and establish a correlation with the corrosion type a multifractal index is calculated.