Electrochemical Properties of Super Austenite Stainless Steel with Temperature in a Green Death Solution

In this investigation, potentiodynamic polarization experiments were conducted on UNS S31603 and UNS N08367 in a modified green death solution, which simulates the environment of a desulfurization device (scrubber), using temperature as a variable. A Tafel analysis showed that the corrosion current density of UNS S31603 at the highest temperature (90 degrees C) was approximately 4.5 times higher than that of UNS N83067. A surface analysis using a scanning electron microscope revealed that pitting and intergranular corrosion occurred simultaneously in UNS S31603, whereas UNS N83067 exhibited a stronger tendency toward intergranular corrosion. After electrochemical experiments, the corrosion rates according to maximum damage depth were compared with the corrosion rates according to corrosion current density; the relationships between the two values were expressed as alpha values. The alpha values of UNS N08367 were higher than those of UNS S31603, indicating that the local damage rate of UNS N08367 was higher.