Correlation Between the Pitting Potential Evolution and σ Phase Precipitation Kinetics in the 2205 Duplex Stainless Steel
Abstract
The aim of this work is to correlate the pitting potential ( E pit) evolution with the kinetics of σ phase precipitation in the 2205 duplex stainless steel aged at 850 °C after solution treatment at 1150 °C. The potentiodynamic polarization curves indicate a reduction of the pitting corrosion resistance with the aging time, which is revealed by a decrease in the E pit values from 0.65 to 0.40 VSCE. Thus, E pit values are used to determine the kinetics parameters of the σ phase precipitation. The experimental transformed fraction agrees well with the one calculated by using the modified Kolmogorov-Johnson-Mehl-Avrami equation with an impingement parameter c = 0.6.