About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
|
Symposium
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High Temperature Oxidation of Metals and Ceramics
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Presentation Title |
The Effect of Pressure on the Oxidation of Steels in Direct-fired Supercritical CO2 Power Cycle Environments |
Author(s) |
Casey Carney, Richard P. Oleksak, Joseph H. Tylczak, Ömer N. Doğan |
On-Site Speaker (Planned) |
Casey Carney |
Abstract Scope |
The effect of elevated pressure on corrosion resistance is a key materials selection concern in direct-fired supercritical CO2 power cycles. Several commercial steels were exposed to direct-fired conditions (95CO2 – 4H2O – 1 O2) at 550 °C h at both atmospheric pressure (0.1 MPa) and supercritical conditions (20 MPa) for over 2,000 hours. Supercritical conditions significantly affected the oxidation behavior, where most of the steels performed worse compared to atmospheric pressure exposures. Most notably, 18Cr-10Ni steels (304H and 347H) formed protective Cr-oxide scales at 0.1 MPa but failed to do so at 20 MPa, where only highly alloyed austenitic steels (309H, 310S, 800) exhibited protective behavior. Increased spallation was observed at high pressure supercritical conditions, whereas little was observed at atmospheric pressure. The mechanisms responsible for these differences in oxidation behavior with pressure changes and the implications for materials selection in direct-fired sCO2 cycles will be discussed. |