On the rhenium segregation at the low angle grain boundary in a single crystal Ni-base superalloy

doi:10.1016/j.scriptamat.2020.03.063

Scripta Materialia

Volume 185, August 2020, Pages 88-93

https://doi.org/10.1016/j.scriptamat.2020.03.063 Get rights and content

Abstract

Industrial scale single crystal (SX) Ni-base superalloys contain numerous low angle grain boundaries inherited from the solidification process. Here, we demonstrate that low angle grain boundaries in a fully heat-treated SX model Ni-base superalloy are strongly segregated with up to 12 at% Re. Some Re-rich dislocations forming this grain boundary are found located inside γ, others close to a γ/γ′ interface. Although these segregated Re atoms lose their solid-solution strengthening effect, they may enhance the creep resistance by pinning the low angle grain boundaries and slowing down dislocation reactions.

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Declaration of Competing Interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

All authors acknowledge the financial support from DFG SFB TR 103 through project A4 and B7. JH and BG are grateful to U. Tezins and A. Sturm for their technical support of the atom probe tomography and focused ion beam facilities at the Max-Planck-Institut für Eisenforschung.

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On the rhenium segregation at the low angle grain boundary in a single crystal Ni-base superalloy

Abstract

Graphical abstract

Section snippets

Declaration of Competing Interests

Acknowledgments

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