Thermal stability and irradiation response of nanocrystalline CoCrCuFeNi high-entropy alloy

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Yanwen Zhang
  • Matheus A. Tunes
  • Miguel L. Crespillo
  • Fuxiang Zhang
  • Walker L. Boldman
  • And 7 others
  • Philip D. Rack
  • Li Jiang
  • Chen Xu
  • Graeme Greaves
  • Stephen E. Donnelly
  • Lumin Wang
  • William J. Weber

External Organisational units

  • Oak Ridge National Laboratory (ORNL)
  • Materials Science and Engineering Department
  • University of Huddersfield
  • University of Michigan, Ann Arbor

Abstract

Grain growth and phase stability of a nanocrystalline face-centered cubic (fcc) Ni0.2Fe0.2Co0.2Cr0.2Cu0.2 high-entropy alloy (HEA), either thermally- or irradiation-induced, are investigated through in situ and post-irradiation transmission electron microscopy (TEM) characterization. Synchrotron and lab x-ray diffraction measurements are carried out to determine the microstructural evolution and phase stability with improved statistics. Under in situ TEM observation, the fcc structure is stable at 300 °C with a small amount of grain growth from 15.8 to ∼20 nm being observed after 1800 s. At 500 °C, however, some abnormal growth activities are observed after 1400 s, and secondary phases are formed. Under 3 MeV Ni room temperature ion irradiation up to an extreme dose of nearly 600 displacements per atom, the fcc phase is stable and the average grain size increases from 15.6 to 25.2 nm. Grain growth mechanisms driven by grain rotation, grain boundary curvature, and disorder are discussed.

Details

Original languageEnglish
Article number294004
JournalNanotechnology
Volume30.2019
Issue number29
DOIs
Publication statusPublished - 1 May 2019
Externally publishedYes