Atom probe tomography of secondary γ′ precipitation in a single crystal Ni-based superalloy after isothermal aging at 1100°C

• Published in: Journal of alloys and compounds 2014-10, Vol.611, p.389-394
• Main Authors: Tan, X.P., Mangelinck, D., Perrin-Pellegrino, C., Rougier, L., Gandin, Ch.-A., Jacot, A., Ponsen, D., Jaquet, V.
• Format: Article
• Language: English
• Subjects: Alloys; Atom probe tomography; Composition fluctuations; Cross-disciplinary physics: materials science; rheology; Engineering Sciences; Exact sciences and technology; High-temperature alloys; Materials; Materials science; Nickel; Nucleation; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Precipitates; Precipitation; Single crystals; Solid solution, precipitation, and dispersion hardening; aging; Superalloys; Tomography; Treatment of materials and its effects on microstructure and properties
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.05.132

[Display omitted] •Bimodal size distribution of γ′ precipitates occurs after isothermal aging at 1100°C.•Characterization of secondary γ′ by atom probe tomography.•It is proposed that the secondary γ′ occurs via a non-classical nucleation.•The coarsening of secondary γ′ precipitates well obeys the classical LSW theory. Secondary γ′ precipitation in a commercial single crystal Ni-based superalloy after the 1100°C isothermal aging has been investigated by atom probe tomography. After the isothermal aging for 300s, 1800s and 3600s, a bimodal size distribution of larger primary γ′ precipitates and numerous smaller secondary γ′ precipitates was obtained. It is proposed that the secondary γ′ precipitated via a non-classical nucleation mode. The coarsening of secondary γ′ precipitates well obeys the classical LSW theory.