Abstract
A nondestructive electrochemical method for estimating the degradation of 347 stainless steel superheater tubes has been investigated using basic electrolytes. It was found that Cr/Fe concentration ratio and the anodic peak current density corresponding to dissolution of precipitates (carbides and sigma phases) in 1m NaOH increased with exposure time at elevated temperatures. The peak current density was observed to increase with electrode surface finish, electrolyte temperature and potential scan rate. A scan rate of 45 mV min−1, temperature below 40° C and surface finish using 1200 grade SiC paper or a mirror finish (3 μm diamond paste) is recommended.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
