| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Environmentally Assisted Cracking: Theory and Practice
|
| Presentation Title |
Microstructural Aspects of the Deterioration of Creep Life for Austenitic Steels in CO2 Environment |
| Author(s) |
Kyle Rozman, Richard Oleksak, Ömer Doğan |
| On-Site Speaker (Planned) |
Kyle Rozman |
| Abstract Scope |
Understanding the interaction between environmental exposure and creep performance of alloys in hot CO2 is important for material selection for supercritical CO2 power cycle technology. Of particular concern is the possibility of alloy carburization in promoting crack propagation and ultimately reducing creep rupture life, especially for thin-walled components. While this has been clearly observed for 9Cr martensitic steels where alloy carburization is substantial, work on more highly alloyed austenitic steels, where carburization rates are much lower, is less clear. This study investigates the creep performance of alloys 347H and 309H in gaseous CO2 at 650 °C. Specimen thickness varied from 0.5 mm to 2 mm. Results indicated a drop in creep life for 347H, while testing for 309H is ongoing. Microstructural investigations of failed specimens suggest that carburization can not only cause precipitation of carbide particles, but also influence martensitic transformations taking place during creep for these metastable austenitic steels. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Temperature Materials, Environmental Effects, Iron and Steel |