Characterization of gamma prime (γ) precipitates in a polycrystalline nickel-base superalloy using small-angle neutron scattering

Research output: Contribution to journalArticlepeer-review

Authors

Colleges, School and Institutes

External organisations

  • University of Cambridge
  • ISIS Facility

Abstract

Small angle neutron scattering (SANS) has been used to evaluate the temporal evolution of the secondary and tertiary γ precipitates in the nickel-base superalloy, RR1000, in situ during an aging heat treatment at 1033 K (760 °C) following a supersolvus heat treatment and oil quench. The bimodal distribution of secondary and tertiary γ was analyzed using a specially developed polydispersive model capable of evaluating the scattering curves to obtain precipitate size distributions (PSDs) and volume fractions as a function of time. The model was designed to be suitable for high volume fractions of γ and takes into account the scattering interaction between precipitates. The results show an increase in the volume fraction and the mean particle size of both the secondary γ and tertiary γ during aging. The initial and final precipitate distributions have been characterized using transmission electron microscopy (TEM) and show satisfactory correlation with the SANS data across the scattering vector range.

Details

Original languageEnglish
Pages (from-to)49-59
Number of pages11
JournalMetallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
Volume42
Issue number1
Publication statusPublished - Jan 2011