{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T23:34:01Z","timestamp":1770420841916,"version":"3.49.0"},"reference-count":55,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,10,29]],"date-time":"2021-10-29T00:00:00Z","timestamp":1635465600000},"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 Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/CTM-CTM\/31579\/2017"],"award-info":[{"award-number":["PTDC\/CTM-CTM\/31579\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/EMS\/00285\/2020"],"award-info":[{"award-number":["UIDB\/EMS\/00285\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metals"],"abstract":"<jats:p>This work aims to investigate the joining of Ti6Al4V alloy to alumina by diffusion bonding using titanium interlayers: thin films (1 \u00b5m) and commercial titanium foils (5 \u00b5m). The Ti thin films were deposited by magnetron sputtering onto alumina. The joints were processed at 900, 950, and 1000 \u00b0C, dwell time of 10 and 60 min, under contact pressure. Experiments without interlayer were performed for comparison purposes. Microstructural characterization of the interfaces was conducted by optical microscopy (OM), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), and electron backscatter diffraction (EBSD). The mechanical characterization of the joints was performed by nanoindentation to obtain hardness and reduced Young\u2019s modulus distribution maps and shear strength tests. Joints processed without interlayer have only been achieved at 1000 \u00b0C. Conversely, joints processed using Ti thin films as interlayer showed promising results at temperatures of 950 \u00b0C for 60 min and 1000 \u00b0C for 10 and 60 min, under low pressure. The Ti adhesion to the alumina is a critical aspect of the diffusion bonding process and the joints produced with Ti freestanding foils were unsuccessful. The nanoindentation results revealed that the interfaces show hardness and reduced Young modulus, which reflect the observed microstructure. The average shear strength values are similar for all joints tested (52 \u00b1 14 MPa for the joint processed without interlayer and 49 \u00b1 25 MPa for the joint processed with interlayer), which confirms that the use of the Ti thin film improves the diffusion bonding of the Ti6Al4V alloy to alumina, enabling a decrease in the joining temperature and time.<\/jats:p>","DOI":"10.3390\/met11111728","type":"journal-article","created":{"date-parts":[[2021,11,1]],"date-time":"2021-11-01T22:22:24Z","timestamp":1635805344000},"page":"1728","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Joining Ti6Al4V to Alumina by Diffusion Bonding Using Titanium Interlayers"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7049-1245","authenticated-orcid":false,"suffix":"Jr.","given":"Marcionilo","family":"Silva","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Federal University of Amazonas, General Rodrigo Octavio Jord\u00e3o Ramos ST, Manaus 69067-005, Brazil"},{"name":"DEMM, Department of Metallurgical and Materials Engineering, University of Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"LAETA\/INEGI, Institute of Science and Innovation in Mechanical and Industrial Engineering, R. Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"University of Coimbra, CEMMPRE, Department of Mechanical Engineering, R. Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8486-5436","authenticated-orcid":false,"given":"Ana S.","family":"Ramos","sequence":"additional","affiliation":[{"name":"University of Coimbra, CEMMPRE, Department of Mechanical Engineering, R. Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4670-4516","authenticated-orcid":false,"given":"S\u00f3nia","family":"Sim\u00f5es","sequence":"additional","affiliation":[{"name":"DEMM, Department of Metallurgical and Materials Engineering, University of Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"LAETA\/INEGI, Institute of Science and Innovation in Mechanical and Industrial Engineering, R. Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Leyens, C., and Peters, M. (2003). Titanium and Titanium Alloys, Wiley.","DOI":"10.1002\/3527602119"},{"key":"ref_2","unstructured":"Carter, C.B., and Norton, M.G. (2007). Ceramic Materials, Springer."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Sim\u00f5es, S. (2018). Recent Progress in the Joining of Titanium Alloys to Ceramics. 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