{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,14]],"date-time":"2025-11-14T21:33:41Z","timestamp":1763156021752,"version":"build-2065373602"},"reference-count":47,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,1]],"date-time":"2018-10-01T00:00:00Z","timestamp":1538352000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PD-BD-52674 2014"],"award-info":[{"award-number":["PD-BD-52674 2014"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metals"],"abstract":"<jats:p>The homogeneity of dispersion and reinforcing of pure aluminium by multi-walled carbon nanotubes (MWCNT) through the application of a high speed sonication (340 Hz) assisted by ultrasonication (35 kHz) was evaluated, this method was termed \u201cassisted sonication\u201d. Other reinforcements (graphene, nanoalumina, and ultrafine tungsten carbide) were used for comparison with the MWCNT. The hardness measurement enabled us to evaluate the strengthening effect of the reinforcements. Raman analysis was the technique selected to evaluate the integrity of MWCNTs during dispersion. The scanning and transmission electron microscopies revealed the dispersion and microstructure of the nanoreinforcements and nanocomposites. After applying the assisted sonication, the MWCNTs were detangled without exfoliation. The integrity of MWCNTs was strongly influenced by the presence of the aluminum powder during dispersion. The application of the assisted sonication method reduced the size of the aggregates in the matrix, in comparison with the sonication technique. Ultrafine tungsten carbide, with a 1 vol. %, was the reinforcement that more effectively hardened aluminum due to a good dispersion of the reinforcement, grain refinement and the formation of Al12W phase.<\/jats:p>","DOI":"10.3390\/met8100786","type":"journal-article","created":{"date-parts":[[2018,10,2]],"date-time":"2018-10-02T11:30:02Z","timestamp":1538479802000},"page":"786","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Effect of Reinforcement Type and Dispersion on the Hardening of Sintered Pure Aluminium"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6722-1866","authenticated-orcid":false,"given":"Omid","family":"Emadinia","sequence":"first","affiliation":[{"name":"CEMMPRE, Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"INEGI-Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua. Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9981-3826","authenticated-orcid":false,"given":"Maria","family":"Vieira","sequence":"additional","affiliation":[{"name":"CEMMPRE, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3667-0562","authenticated-orcid":false,"given":"Manuel","family":"Vieira","sequence":"additional","affiliation":[{"name":"CEMMPRE, Department of Metallurgical and Materials Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"INEGI-Institute of Science and Innovation in Mechanical and Industrial Engineering, Rua. Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"798","DOI":"10.1007\/s40195-014-0154-z","article-title":"Manufacture of nano-sized particle-reinforced metal matrix composites: A review","volume":"27","author":"Zhou","year":"2014","journal-title":"Acta Metall. Sin. Engl. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1179\/095066009X12572530170543","article-title":"Carbon nanotube reinforced metal matrix composites-a review","volume":"55","author":"Bakshi","year":"2010","journal-title":"Inter. Mater. 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