The corrosion behaviors of carbon and stainless steels were investigated in supercritical CO₂ (sCO₂ ) containing H₂O and O₂ simulating conditions that exist in direct sCO₂ power cycle heat exchangers. Thermodynamic properties of CO₂-H₂O-O₂ systems related to the corrosion phenomena were determined using NIST software. The exposure tests of the...