Time-lapse observation of pitting corrosion in ferritic stainless steel under bipolar electrochemistry control

A bipolar electrochemistry approach has been applied to characterise pit nucleation and growth kinetics in 13% Cr ferritic stainless steel. In-situ time-lapse imaging, supported by laser confocal microscopy measurements, were applied to obtain pit nucleation frequencies and associated pit growth characteristics. The development of champion pits is observed, and the effect of pit shape and aspect ratio on pit nucleation and growth are discussed. Pits preferentially nucleated and grew with depth to width aspect ratios of 0.4-0.6. The observed pit growth kinetics are independent of pit volume and the acting potentials.

Automated summary

A bipolar electrochemistry approach was used to characterize pit nucleation and growth kinetics in 13% Cr ferritic stainless steel. Pits were found to preferentially nucleate and grow with depth to width aspect ratios of 0.4-0.6, and the observed pit growth kinetics were independent of pit volume and the acting potentials.