{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,25]],"date-time":"2026-01-25T23:06:37Z","timestamp":1769382397762,"version":"3.49.0"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,10,31]],"date-time":"2018-10-31T00:00:00Z","timestamp":1540944000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>CoCrFeCuNi high-entropy alloys (HEAs) prepared by arc melting were irradiated with a 100 keV He+ ion beam. Volume swelling and hardening induced by irradiation were evaluated. When the dose reached 5.0 \u00d7 1017 ions\/cm2, the Cu-rich phases exhibited more severe volume swelling compared with the matrix phases. This result indicated that the Cu-rich phases were favorable sites for the nucleation and gathering of He bubbles. X-ray diffraction indicated that all diffraction peak intensities decreased regularly. This reduction suggested loosening of the irradiated layer, thereby reducing crystallinity, under He+ ion irradiation. The Nix-Gao model was used to fit the measured hardness in order to obtain a hardness value H0 that excludes the indentation size effect. At ion doses of 2.5 \u00d7 1017 ions\/cm2 and 5.0 \u00d7 1017 ions\/cm2, the HEAs showed obvious hardening, which could be attributed to the formation of large amounts of irradiation defects. At the ion dose of 1.0 \u00d7 1018 ions\/cm2, hardening was reduced, owing to the exfoliation of the original irradiation layer, combined with recovery induced by long-term thermal spike. This study is important to explore the potential uses of HEAs under extreme irradiation conditions.<\/jats:p>","DOI":"10.3390\/e20110835","type":"journal-article","created":{"date-parts":[[2018,10,31]],"date-time":"2018-10-31T11:55:41Z","timestamp":1540986941000},"page":"835","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Evaluation of Radiation Response in CoCrFeCuNi High-Entropy Alloys"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9877-0182","authenticated-orcid":false,"given":"Yang","family":"Wang","sequence":"first","affiliation":[{"name":"Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Kun","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Yihui","family":"Feng","sequence":"additional","affiliation":[{"name":"School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China"}]},{"given":"Yansen","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Weiqi","family":"Tang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Bingchen","family":"Wei","sequence":"additional","affiliation":[{"name":"Key Laboratory of Microgravity (National Microgravity Laboratory), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.pmatsci.2013.10.001","article-title":"Microstructures and properties of high-entropy alloys","volume":"61","author":"Zhang","year":"2014","journal-title":"Prog. 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