{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T03:02:13Z","timestamp":1771902133148,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T00:00:00Z","timestamp":1765497600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study reports the successful fabrication and application of floatable syntactic foams derived from fine magnesium powder (&lt;45 \u00b5m) utilizing expanded perlite (0.25 g\/cm3, 0.2\u20130.4 mm) as the pore former. Sample disks with densities as low as 0.9 g\/cm3 were produced via the classical press and sinter process. To ensure reasonable mechanical properties, the specimens were formed under a pressure of 200 MPa in a hardened steel die, followed by high-vacuum sintering (~3 \u00d7 10\u22126 torr) at 640 \u00b0C for 1 h. The resulting foams exhibited sufficient mechanical strength to allow for precision machining into a microboat. We demonstrated their potential use as a Marangoni-induced microswimmer. Spontaneous locomotion was observed when ethanol was used as a propellant, which generates a surface tension gradient between the upper and rear parts of the swimmer. The microboats achieved propulsion speeds of approximately 160 mm\/s when propelled by a 95% ethanol + 5% ink mixture. Using a small volume (~4 \u00b5L) of the alcohol mixture, the swimmer could cover distances exceeding 350 mm.<\/jats:p>","DOI":"10.3390\/ma18245588","type":"journal-article","created":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T12:52:31Z","timestamp":1765543951000},"page":"5588","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Floatable Syntactic Magnesium Foam as a Marangoni-Induced Propulsion Microboat"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2762-6110","authenticated-orcid":false,"given":"Gyorgy","family":"Thalmaier","sequence":"first","affiliation":[{"name":"Material Science and Engineering Departament, Materials and Environmental Engineering Faculty, Technical University of Cluj-Napoca, 103 Muncii Blv., 400641 Cluj-Napoca, Romania"},{"name":"Institute of Nanomaterials and Nanotechnologies\u2014Eutinn, European University of Technology, European Union, 28 Memorandumului Street, 400114 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-5941-3843","authenticated-orcid":false,"given":"Niculina Argentina","family":"Sechel","sequence":"additional","affiliation":[{"name":"Material Science and Engineering Departament, Materials and Environmental Engineering Faculty, Technical University of Cluj-Napoca, 103 Muncii Blv., 400641 Cluj-Napoca, Romania"},{"name":"Institute of Nanomaterials and Nanotechnologies\u2014Eutinn, European University of Technology, European Union, 28 Memorandumului Street, 400114 Cluj-Napoca, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4663-0652","authenticated-orcid":false,"given":"Ioan","family":"Vida-Simiti","sequence":"additional","affiliation":[{"name":"Material Science and Engineering Departament, Materials and Environmental Engineering Faculty, Technical University of Cluj-Napoca, 103 Muncii Blv., 400641 Cluj-Napoca, Romania"},{"name":"Technical Science Academy of Romania, Dacia Ave., 26, 010413 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1007\/s11837-000-0062-8","article-title":"Manufacturing Routes for Metallic Foams","volume":"52","author":"Banhart","year":"2000","journal-title":"JOM"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1016\/S0079-6425(00)00002-5","article-title":"Manufacture, Characterization and application of cellular metals and metal foams","volume":"46","author":"Banhart","year":"2001","journal-title":"Prog. 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