About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
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Symposium
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Materials for High Temperature Applications: Next Generation Superalloys and Beyond
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Presentation Title |
Low Cycle Fatigue of Single Crystal Co- and CoNi-base Superalloys: The Role of Oxidation Resistance |
Author(s) |
Sean P. Murray, Alice Cervellon, Jean-Charles Stinville, Jonathan Cormier, Tresa Pollock |
On-Site Speaker (Planned) |
Sean P. Murray |
Abstract Scope |
γ-containing Co- and CoNi-base superalloys are promising candidate materials for high temperature, high stress applications. The first studies on the low cycle fatigue resistance of single crystal Co-base superalloys revealed that their insufficient oxidation resistance leads to early fatigue failures in air, even with the addition of an aluminide coating. CoNi-base superalloy compositions have a more flexible design space, allowing for alloying additions that promote the formation of protective oxide scales after high temperature exposure such as α-Al2O3. A novel single crystal single crystal superalloy SB-CoNi-10+ has been investigated in the low cycle regime under load-control, R=-1, at T=950 °C in both laboratory air and under high vacuum. Under these conditions, the alloy has LCF rupture life comparable to Ni-base single crystal alloy AM1 in air and has excellent performance under high vacuum. Stress-strain response, fracture surface analysis, and microstructural investigations of the post-mortem specimens will be discussed. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Environmental Effects, High-Temperature Materials |