Electrochemical and corrosion behavior of a 304 stainless-steel-based metal alloy wasteform in dilute aqueous environments

摘要

The electrochemical and corrosion behavior of a stainless-steel-based alloy made as a prototype metallic nuclear wasteform to immobilize ~(99)Tc, has been studied in a number of reference solutions ranging in pH from 4 to 10. The results showed the 47SS(304)-9Zr-23Mo prototype alloy contained at least five distinct phases with the majority of the Re, used as a Tc surrogate, contained within a Fe_2Mo intermetallic phase. Polarization studies showed this alloy exhibited generally passive behavior in a range of dilute aqueous environments. Impedance measurements indicated passivity breakdown events can occur and lead to localized corrosion, especially in slightly alkaline conditions.