Oxidation of alloys for energy applications in supercritical CO2 and H2O

Abstract To facilitate development of supercritical CO 2 (sCO 2 ) power plants, a comparison of the oxidation behavior of austenitic stainless steels and Ni-base alloys in sH 2 O and sCO 2 were made. Experiments were conducted at 730 °C/207 bar (sCO 2 ) and 726 °C/208 bar (sH 2 O). Ni-base alloys in sCO 2 did not exhibit much change with pressure. Ni-base alloys in sH 2 O had an increase in corrosion rate and the log of the parabolic rate constant was proportional to pressure. Fine-grain austenitic stainless steels in sCO 2 and sH 2 O were both less protective with pressure as the dense protective chromia scale was replaced with faster growing Fe-oxide rich scales.