He-enhanced heterogeneity of radiation-induced segregation in FeNiCoCr high-entropy alloy

Lin，W. T.1; Yeli，G. M.2; Wang，G.3; Lin，J. H.3; Zhao，S. J.1; Chen，D.1,4; Liu，S. F.1; Meng，F. L.5; Li，Y. R.1,6; He，F.1; Lu，Y.1,7; Kai，J. J.1,4

2022-02-28

10.1016/j.jmst.2021.05.053

JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY   影响因子和分区

1005-0302

Radiation-induced segregation (RIS) is a typical non-equilibrium process that can dramatically alter the behavior of defect sinks and material properties under irradiation. However, RIS mechanisms have been rarely studied around small He bubbles owing to the technical challenges involved in direct measurements of local chemistry. Here, using state-of-the-art atom probe tomography, we report the RIS behavior near He bubbles in the FeNiCoCr high-entropy alloy that indicates Co segregates most strongly, followed by weaker Ni segregation, whereas Fe and Cr are depleted almost to the same degree. Exceptionally, the magnitude of Co segregation around He bubbles is higher than previously measured values at voids and dislocation loops. Electron energy-loss spectroscopy was used to measure the He density and pressure inside individual bubbles. We demonstrate that He bubbles are over-pressurized at the irradiation temperature that could result in the vacancy bias and the subsequent vacancy-dominated RIS mechanism. First-principles calculations further reveal that there are repulsive interactions between He and Co atoms that may reduce the frequency of Co-vacancy exchange. As a result, He atoms likely retard Co diffusion via the vacancy mechanism and enhance the heterogeneity of RIS in Co-containing multicomponent alloys. These insights could provide the basis for understanding He effects in nuclear materials and open an avenue for tailoring the local chemical order of medium-and high-entropy alloys.

Atom probe tomography Electron energy-loss spectroscopy He bubbles High-entropy alloy Radiation-induced segregation

SCI ; EI

英语

其他

Hong Kong Research Grant Council["CityU11214820","CityU11205018"] ; National Natural Science Foundation of China (NSFC)[11922215] ; Natural Science Foundation of Guangdong Province in China[2019A1515011836] ; National Natural Science Foundation of China[11974156] ; Guangdong International Science Collaboration Project[2019A050510001]

Materials Science ; Metallurgy & Metallurgical Engineering

Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering

WOS:000766627700006

JOURNAL MATER SCI TECHNOL

20213710891787

Atoms ; Calculations ; Chromium alloys ; Chromium metallography ; Cobalt alloys ; Electron energy levels ; Electron energy loss spectroscopy ; Electron scattering ; Energy dissipation ; Entropy ; Helium ; High-entropy alloys ; Interlocking signals ; Iron alloys ; Iron metallography ; Irradiation ; Multilayers ; Nickel metallography ; Segregation (metallography)

Energy Losses (industrial and residential):525.4 ; Metallography:531.2 ; Chromium and Alloys:543.1 ; Iron Alloys:545.2 ; Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals:549.3 ; Thermodynamics:641.1 ; Railroad Signals and Signaling:681.3 ; Chemical Products Generally:804 ; Mathematics:921 ; Atomic and Molecular Physics:931.3

MATERIALS SCIENCE

2-s2.0-85114706317

Scopus

1.Department of Mechanical Engineering,City University of Hong Kong,Hong Kong,Hong Kong
2.Institute of Nuclear & New Energy Technology,Tsinghua University,China
3.Department of Physics,Southern University of Science and Technology,Shenzhen,China
4.Centre for Advanced Nuclear Safety and Sustainable Development,City University of Hong Kong,Hong Kong,Hong Kong
5.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,China
6.School of Materials Science and Engineering,Shanghai University,China
7.Nano-Manufacturing Laboratory (NML),City University of Hong Kong Shenzhen Research Institute,Shenzhen,China

Lin，W. T.,Yeli，G. M.,Wang，G.,et al. He-enhanced heterogeneity of radiation-induced segregation in FeNiCoCr high-entropy alloy[J]. JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,2022,101:226-233.

Lin，W. T..,Yeli，G. M..,Wang，G..,Lin，J. H..,Zhao，S. J..,...&Kai，J. J..(2022).He-enhanced heterogeneity of radiation-induced segregation in FeNiCoCr high-entropy alloy.JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,101,226-233.

Lin，W. T.,et al."He-enhanced heterogeneity of radiation-induced segregation in FeNiCoCr high-entropy alloy".JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY 101(2022):226-233.