On the diffusion mechanisms of fine-scale γ ′ in an advanced Ni-based superalloy

Y. Chen, E. M. Francis, M. Preuss, S. J. Haigh

Research output: Chapter in Book/Report/Conference proceedingConference PaperOther

1 Citation (Scopus)


Size dependent compositional variations for the ordered L1 2-structure gamma prime (γ′) precipitates in the commercial Ni-based superalloy RR1000 have been investigated using scanning transmission electron microscope (STEM) imaging combined with energy-dispersive X-ray (EDX) spectroscopy. To address the problem of quantitative compositional determination for nanoscale particles within a metal matrix we have applied a novel electrochemical method to extract individual precipitates. The use of a high-efficiency EDX detector enabled compositional measurements to be obtained for particles with diameters as small as 20 nm with acquisition times of the order of a few minutes. We have studied compositional variations across the different size families of γ′ precipitates within a microstructure generated by slow cooling. Our results demonstrate the importance of kinetic factors for determining the precipitates compositions. In particular, we provide new evidence for the role of aluminium antisite atoms on the low-temperature growth kinetics of fine scale γ′ precipitates. Our findings provide valuable structural data towards improving the accuracy of predicting the microstructural evolution in Ni-based superalloys.

Original languageEnglish
Title of host publicationEUROSUPERALLOYS 2014
Subtitle of host publication2nd European Symposium on Superalloys and their Applications
Number of pages5
Publication statusPublished - 2014
Externally publishedYes
EventEuropean Symposium on Superalloys and Their Applications 2014 - Giens, France
Duration: 12 May 201416 May 2014
Conference number: 2nd

Publication series

NameMATEC Web of Conferences
PublisherEDP Sciences
ISSN (Print)2261-236X


ConferenceEuropean Symposium on Superalloys and Their Applications 2014
Abbreviated titleEUROSUPERALLOYS 2014
Internet address

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