{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T10:01:19Z","timestamp":1789984879595,"version":"4.0.1"},"reference-count":51,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>This study investigates the effect of mechanically alloyed AlCrFeCuNi high-entropy alloy (HEA) reinforcement with a nanocrystalline internal structure on the microstructural, mechanical, electrical, and tribological properties of Cu\u20131 wt.% B4C composites containing 0\u201330 wt.% HEA. The AlCrFeCuNi reinforcement used in this work had previously been produced by 25 h of mechanical alloying and characterized in detail, exhibiting a dual FCC\u2013BCC structure and an average crystallite size of 10.2 nm while retaining micrometer-scale particle dimensions. The Cu\u2013B4C\u2013HEA powder mixtures were subsequently milled and consolidated by spark plasma sintering at 800 \u00b0C under 35 MPa. Increasing the HEA content progressively refined the powder mixture and increased the hardness from 78.8 HB for 0HEA to 138.94 HB for 20HEA, while the latter retained a relative density of 96.1% and an electrical conductivity of 67% IACS. The 20HEA composite exhibited the lowest average friction coefficient (0.36) and specific wear rate (1.01 \u00d7 10\u22123 mm3\/N\u00b7m), corresponding to an approximately 88% reduction in wear rate relative to 0HEA. Microstructural and worn-surface analyses showed that this behavior was associated with the combined effects of hard HEA reinforcement, preserved Cu-matrix continuity, and the formation of an oxygen-rich mechanically mixed layer. Increasing the HEA content to 30 wt.% promoted reinforcement clustering and residual porosity, which reduced densification and partially deteriorated the tribological performance.<\/jats:p>","DOI":"10.3390\/nano16181190","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T08:03:47Z","timestamp":1789977827000},"page":"1190","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of AlCrFeCuNi High-Entropy Alloy Reinforcement with a Nanocrystalline Internal Structure on the Microstructure, Electrical Conductivity and Tribological Behavior of SPS-Processed Cu\u2013B4C Composites"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1826-5379","authenticated-orcid":false,"given":"M\u00fcslim","family":"\u00c7elebi","sequence":"first","affiliation":[{"name":"Department of Metallurgical and Materials Engineering, Faculty of Engineering, Karadeniz Technical University, 61080 Trabzon, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"180959","DOI":"10.1016\/j.jallcom.2025.180959","article-title":"Role of High-Entropy Alloys in Enhancing the Properties of Copper Matrix Composites: A Study on Mechanical and Thermoelectric Behavior","volume":"1030","author":"Zhang","year":"2025","journal-title":"J. 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