Rescaled range analysis of the corrosion potential noise

Rescaled range (R=S) analysis of random events is known to reveal the persistent or anti- persistent nature of the process. Time records of corrosion potential noise, i.e. spontaneous voltage fluctuations with zero current, were collected from freely corroding pure aluminium samples in a number of different electrolytes. The results of the R=S analysis, also compared with those of simulated time series, revealed long term correlations, the nature of which were seen to be characteristic to the corrosion processes. The differences between the R=S patterns of general and pitting corrosion have been found to be particularly distinctive. 2002 Elsevier Science Ltd. All rights reserved.