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 |
Partitioning of Cu and Si Contaminants in a Ni-based Superalloy and their Effect on Creep Properties |
Author(s) |
Martin Detrois, Zongrui Pei, Kyle Rozman, Michael Gao, Jonathan Poplawsky, Paul Jablonski, Jeffrey Hawk |
On-Site Speaker (Planned) |
Martin Detrois |
Abstract Scope |
The choice of stock material to form an alloy composition affects the overall purity of the final product. Two Al raw material sources were selected for incorporation into an advanced Ni-based superalloy which resulted in low purity alloys (containing 0.138 wt.% Cu and 0.019 wt.% Si) and high-purity alloys (containing less than 0.003 wt.% Cu and 0.010 wt.% Si). Atom-probe tomography (APT) revealed Si partitioning at the grain boundaries, MC-carbide/γ, M3B2-boride/γ-γ′. Copper primarily segregated to the γ′ precipitates. An average of 2.4x decrease in creep life and 4.3x decrease in creep ductility was measured in the low purity alloys, which was attributed to the embrittlement caused by Si segregation to grain boundaries. Furthermore, Si reduced the positive effect of B segregation to grain boundaries on creep performance. Monte Carlo simulations were performed to describe the partitioning of Cu and Si atoms to either γ or γ′ phases. |
Proceedings Inclusion? |
Planned: |