Segregation-induced strength anomalies in complex single-crystalline superalloys

Bezold A, Vollhüter J, Karpstein N, Lenz M, Subramanyam AP, Zenk C, Hammerschmidt T, Spiecker E, Göken M, Neumeier S (2024)


Publication Language: English

Publication Type: Journal article

Publication year: 2024

Journal

Book Volume: 5

Article Number: 8

DOI: 10.1038/s43246-024-00447-x

Abstract

Pushing the maximum service temperature of aircraft engines and industrial gas turbines is the major pathway to improve their energy efficiency and reduce CO2 emissions. This maximum is mostly limited by the temperature capability of key-component materials, including superalloys. In this alloy class, segregation of elements facilitates plastic deformation and is generally considered to cause softening during high-temperature deformation. Here, we show that segregation-assisted processes can also lead to strengthening and induce an anomalous increase of the yield strength. Atomic-resolution transmission electron microscopy and density functional theory calculations reveal a segregation-assisted dissociation process of dislocations at precipitate-matrix interfaces in combination with atomic-scale reordering processes. These processes lead to an inhibition of athermal deformation mechanisms and a transition to stacking fault shearing, which causes the strengthening effect. Unraveling these elementary mechanisms might guide a mechanism-based alloy design of future superalloys with enhanced high-temperature capabilities.

Authors with CRIS profile

Additional Organisation(s)

Involved external institutions

How to cite

APA:

Bezold, A., Vollhüter, J., Karpstein, N., Lenz, M., Subramanyam, A.P., Zenk, C.,... Neumeier, S. (2024). Segregation-induced strength anomalies in complex single-crystalline superalloys. Communications Materials, 5. https://doi.org/10.1038/s43246-024-00447-x

MLA:

Bezold, Andreas, et al. "Segregation-induced strength anomalies in complex single-crystalline superalloys." Communications Materials 5 (2024).

BibTeX: Download