Intermetallic Phases Formation During Short Aging between 850°C and 950°C of a Superduplex Stainless Steel

This paper is based on the study of intermetallic phase formation during aging between 850°C and 950°C, for periods up to 5 min; those treatments were conducted in liquid aluminum bath, allowing fast heating of the small sized specimens. It was found that backscattered electron images could be used in the automatized routines of quantitative stereology of intermetallic phases and nitrides found in duplex and superduplex stainless steels. A measurable intermetallic phase fraction was observed just after 1 min aging in the studied temperatures, but it was not possible to distinguish sigma and chi phases from the observed intermetallic phases. Nitrides were also observed, but they were probably formed in steel manufacturing, since there was no significant influence of aging on its volume fraction.