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

Autor: Zhang Y; Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America. Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, United States of America., Tunes MA, Crespillo ML, Zhang F, Boldman WL, Rack PD, Jiang L, Xu C, Greaves G, Donnelly SE, Wang L, Weber WJ
Jazyk: angličtina
Zdroj: Nanotechnology [Nanotechnology] 2019 Jul 19; Vol. 30 (29), pp. 294004. Date of Electronic Publication: 2019 Apr 04.
DOI: 10.1088/1361-6528/ab1605
Abstrakt: Grain growth and phase stability of a nanocrystalline face-centered cubic (fcc) Ni 0.2 Fe 0.2 Co 0.2 Cr 0.2 Cu 0.2 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.
Databáze: MEDLINE