| About this Abstract |
| Meeting |
2019 TMS Annual Meeting & Exhibition
|
| Symposium
|
Gamma (FCC)/Gamma-Prime (L12) Co-Based Superalloys III
|
| Presentation Title |
The Formation of Protective Alumina on γ’-Strengthened Co-Ni-Al-Mo-Ta Alloys during Exposure at Elevated Temperatures |
| Author(s) |
Saurabh Mohan Das, Mahander Pratap Singh, Om Puri Gosain, Kamanio Chattopadhyay |
| On-Site Speaker (Planned) |
Saurabh Mohan Das |
| Abstract Scope |
L12 precipitate-strengthened Co-base alloys with a basic composition of Co-Ni-Al-Mo-Ta attract attention due to their similar microstructure and comparable solvus temperature and low density to Ni-base superalloys. The present paper discusses the further development of this new series of alloys to have better environment resistance during exposure at high temperature. This includes the high temperature oxidation behavior at different temperatures (650-1000°C) of this alloy and improvement of oxidation resistance by further additions of alloying elements like Ti and Cr with varying concentration without hampering solvus temperature and long term microstructural stability. In the base composition, there is a formation of amorphous alumina at oxide/matrix interface. It was observed that there is a minimum concentration of Cr that is required for the formation of crystalline and protective alumina. Further addition of Cr leads to rapid formation of continuous alumina and hence a drastic reduction in oxidation rate could be observed. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |