| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Advances in High-Temperature Oxidation and Degradation of Materials for Harsh Environments: A SMD and FMD Symposium Honoring Brian Gleeson
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| Presentation Title |
Effects of Steam, Carbon Dioxide, and Oxygen Potential on the Alumina-Scale Establishment Process for Ni-Based Alloys |
| Author(s) |
Jonathan Locker, Brian Gleeson |
| On-Site Speaker (Planned) |
Jonathan Locker |
| Abstract Scope |
As power generation systems move towards higher operating temperatures to increase their efficiency, there is an increasing need for the use of alumina-scale forming alloys. The presence of steam and CO2 has been shown to disrupt protective oxide scale formation, imposing further constraints on alloy compositions in these environments. To explore this important aspect, a commercial alumina forming Ni-based superalloy (Rene N5) and homogenized model Ni-6Al-XCr (X: 2, 4, 6, 8, 10 at.%) alloys were exposed to Ar, Ar+20% H2O, and Ar+4%CO2 environments at 1200 °C. Preliminary results show that while the lower Cr containing model alloys are predicted to exhibit internal oxidation behavior in air, the low PO2 of the Ar atmosphere produces drastic changes in the critical aluminum concentration necessary for the transition between internal-external oxidation behavior. This is further complicated in the steam and CO2-containing environments. |