Abstract

Pitting corrosion is particularly dangerous due to its localised nature, which can render materials unusable and cause catastrophic failures. It is important to characterise the material in regard to pitting corrosion resistance in order to improve material selection according to the conditions of the exposed environment. Electrochemical tests were carried out to assess pitting corrosion in austenitic stainless steel EN 1.4301. This study identifies the optimal experimental conditions to ensure reliability and reproducibility in electrochemical tests. The results demonstrate the influence of these parameters in evaluating the resistance of stainless steels to pitting corrosion. To ensure the reproducibility of the breakdown potential (Eb), deaeration was standardised using an N2 flow rate of 0.6–0.8 L/min for 20 min. Furthermore, mechanical agitation at 280 rpm was established as a necessary condition to homogenise the electrolyte and effectively renew the metal/solution interface. Finally, the water flow rate was set at a critical value of 7 mL/h, statistically identified as the most decisive parameter (p < 0.05). This optimisation mitigates crevice corrosion, ensuring that damage nucleation occurs exclusively via a pitting mechanism.

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