Microstructural degradation of polycrystalline superalloys from oxidized carbides and implications on crack initiation
Research output: Contribution to journal › Article › peer-review
Authors
Colleges, School and Institutes
External organisations
- Max-Planck-Institut für Eisenforschung
- Department of Materials, University of Oxford
Abstract
Surface connected carbides in a polycrystalline superalloy oxidized at 750 °C in air were studied as potential crack initiation sites. Lattice rotations measured in the γ/γ′ grains using high-resolution electron backscatter diffraction enabled investigation of the plastic deformation induced solely by the oxidation of carbides. Dislocations were found to enhance γ′ precipitate dissolution kinetics, resulting in soft recrystallized regions in the vicinity of the oxidized carbide with substantial compositional variation compared to the original γ/γ′ microstructure. Ramifications of such deleterious oxidized carbides alongside soft recrystallized regions on the crack initiation life in superalloys are discussed.
Details
Original language | English |
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Pages (from-to) | 59-63 |
Number of pages | 5 |
Journal | Scripta Materialia |
Volume | 147 |
Early online date | 8 Jan 2018 |
Publication status | Published - 1 Apr 2018 |
Keywords
- Atom probe tomography, Oxidized carbides, Partial dislocation, Recrystallization, γ′ Dissolution