Determination of Tafel slopes from coulostatically induced transients using an integral algorithm

The analysis of coulostatically induced transients (CITs) has been used as a tool to evaluate the corrosion rate of metallic materials, and a new algorithm has been developed to calculate the Tafel slopes (ba and bc). This new algorithm is based on the coulostatic strong polarization integration (CSPI) method. Experimental results for carbon steels exposed to 0.5 M H2SO and 1 M HCl show excellent agreement between the proposed method and the Tafel line extrapolation method with IR drop correction. Furthermore, the calculated average corrosion currents over 8 h tests are in good agreement with solution analysis data from atomic absorption spectroscopy. The improved CSPI algorithm shows superior performance over the differential algorithm and the conventional algorithm due to its simplicity and higher signal/noise ratio.