{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T04:52:31Z","timestamp":1781844751626,"version":"3.54.5"},"reference-count":31,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T00:00:00Z","timestamp":1781308800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"DFG","award":["INST 186\/1367-1 FUGG"],"award-info":[{"award-number":["INST 186\/1367-1 FUGG"]}]},{"name":"DFG","award":["INST 186\/1522-1 FUGG"],"award-info":[{"award-number":["INST 186\/1522-1 FUGG"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>The ultra-short-pulse (USP) laser joining of sapphire to iron is investigated by combining electron backscatter diffraction (EBSD) and ruby (Cr3+) R1 fluorescence mapping to resolve the joint microstructure and pressure distributions. Energy-dispersive X-ray spectroscopy (EDS) reveals Al, O, and Fe intermixing within the seam, consistent with the formation of thin Fe\u2013Al\u2013O reaction layers. R1 fluorescence yields a maximum internal pressure of (490\u00b180) MPa within the modified sapphire region and decays to near-zero within a few micrometres distance from the seam. EBSD data suggest a single-crystal sapphire lattice with localized disorientation adjacent to the joint, whereas the iron foil remains polycrystalline with rolling-induced misorientation without additional weld-induced grain refinement. These results demonstrate that USP joining of sapphire to iron produces localized interfacial reaction zones, with confined pressure predominantly occurring within sapphire.<\/jats:p>","DOI":"10.3390\/nano16120737","type":"journal-article","created":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T05:56:31Z","timestamp":1781675791000},"page":"737","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Microstructural Properties and Pressure Distribution in Ultra-Short-Pulse Welds of Sapphire to Iron"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-0152-1512","authenticated-orcid":false,"given":"Lukas","family":"G\u00fcnther","sequence":"first","affiliation":[{"name":"Department Werkstoffwissenschaften, Institut f\u00fcr Glas und Keramik, Friedrich-Alexander-Universitat Erlangen-N\u00fcrnberg (FAU), Martensstra\u00dfe 5, 91058 Erlangen, Germany"},{"name":"SCHOTT AG, Hattenbergstra\u00dfe 10, 55122 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-9202-4278","authenticated-orcid":false,"given":"Anne","family":"Friedrich","sequence":"additional","affiliation":[{"name":"Analytical Mineralogy, Institute of Geosciences, Friedrich Schiller University Jena, Lessingstra\u00dfe 14, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-9194-4967","authenticated-orcid":false,"given":"Jens Ulrich","family":"Thomas","sequence":"additional","affiliation":[{"name":"SCHOTT AG, Hattenbergstra\u00dfe 10, 55122 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1045-2110","authenticated-orcid":false,"given":"Thomas","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Geoscience Centre, Georg-August-Universit\u00e4t G\u00f6ttingen, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9621-4609","authenticated-orcid":false,"given":"Dominique","family":"de Ligny","sequence":"additional","affiliation":[{"name":"Department Werkstoffwissenschaften, Institut f\u00fcr Glas und Keramik, Friedrich-Alexander-Universitat Erlangen-N\u00fcrnberg (FAU), Martensstra\u00dfe 5, 91058 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S297","DOI":"10.3103\/S1068335624601225","article-title":"Study on the Effect of Focusing Parameters of Ultrashort Pulses on the Process of Laser Welding of Transparent Materials with Metals","volume":"51","author":"Murzakov","year":"2024","journal-title":"Bull. 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