{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T12:31:08Z","timestamp":1775737868063,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T00:00:00Z","timestamp":1753228800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"U.S. Department of Energy (DOE)","award":["DE-SC0017138"],"award-info":[{"award-number":["DE-SC0017138"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Refractory high-entropy alloys (HEAs) are promising candidates for next-generation nuclear applications, particularly fusion reactors, due to their excellent high-temperature mechanical properties and irradiation resistance. Here, the microstructure and mechanical behavior were investigated for an equimolar WTaTiVZr HEA, designed from a palette of low-activation elements. The as-cast alloy exhibited a dendritic microstructure composed of W-Ta rich dendrites and Zr-Ti-V rich inter-dendritic regions, both possessing a body-centered cubic (BCC) crystal structure. Room temperature bulk compression tests showed ultra-high strength of around 1.6 GPa and plastic strain ~6%, with fracture surfaces showing cleavage facets. The alloy also demonstrated excellent high-temperature strength of ~650 MPa at 500 \u00b0C. Scratch-based fracture toughness was ~38 MPa\u221am for the as-cast WTaTiVZr HEA compared to ~25 MPa\u221am for commercially used pure tungsten. This higher value of fracture toughness indicates superior damage tolerance relative to commercially used pure tungsten. These results highlight the alloy\u2019s potential as a low-activation structural material for high-temperature plasma-facing components (PFCs) in fusion reactors.<\/jats:p>","DOI":"10.3390\/e27080777","type":"journal-article","created":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T10:49:17Z","timestamp":1753267757000},"page":"777","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["High Strength and Fracture Resistance of Reduced-Activity W-Ta-Ti-V-Zr High-Entropy Alloy for Fusion Energy Applications"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-5700-3704","authenticated-orcid":false,"given":"Siva Shankar","family":"Alla","sequence":"first","affiliation":[{"name":"Department of Materials Science and Engineering, University of North Texas, Denton, TX 76203, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Blake Kourosh","family":"Emad","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, University of North Texas, Denton, TX 76203, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1954-0045","authenticated-orcid":false,"given":"Sundeep","family":"Mukherjee","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, University of North Texas, Denton, TX 76203, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/S0022-3115(02)01175-3","article-title":"Plasma facing and high heat flux materials Plasma facing and high heat flux materials-needs for ITER and beyond","volume":"307","author":"Bolt","year":"2002","journal-title":"J. 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