{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T09:43:11Z","timestamp":1773308591262,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,24]],"date-time":"2024-02-24T00:00:00Z","timestamp":1708732800000},"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":["2022.12317.BD"],"award-info":[{"award-number":["2022.12317.BD"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Adhesive bonding has been increasingly employed in multiple industrial applications. This has led to a large industrial demand for faster, simpler, and cheaper characterization methods that allow engineers to predict the mechanical behavior of an adhesive with numerical models. Currently, these characterization processes feature a wide variety of distinct standards, specimen configurations, and testing procedures and require deep knowhow of complex data-reduction schemes. By suggesting the creation of a new and integrated experimental tool for adhesive characterization, it becomes possible to address this problem in a faster and unified manner. In this work, following a previous numerical study, the mode I and II components of fracture-toughness characterization were validated experimentally in two different configurations, Balanced and Unbalanced. For mode I, it was demonstrated that both configurations presented similar numerical and experimental R-curves. The relative error against standard tests was lower than \u00b15% for the Balanced specimen; the Unbalanced system showed higher variations, which were predicted by the numerical results. Under mode II, the Balanced specimen displayed plastic deformation due to high deflections. On the contrary, the Unbalanced specimen did not show this effect and presented a relative error of approximately \u00b12%. Nonetheless, it was proven that this approach to obtain such data by using a single unified specimen is still feasible but needs further development to obtain with similar precision of standard tests. In the end, a conceptual change is proposed to solve the current mode II issues.<\/jats:p>","DOI":"10.3390\/ma17051049","type":"journal-article","created":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T03:34:04Z","timestamp":1708918444000},"page":"1049","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Development of a Unified Specimen for Adhesive Characterization\u2014Part 2: Experimental Study on the Mode I (mDCB) and II (ELS) Fracture Components"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3458-7404","authenticated-orcid":false,"given":"Daniel S.","family":"Correia","sequence":"first","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), University of Porto, Rua Dr. Roberto Frias 400, 4200-465 Porto, Portugal"}]},{"given":"In\u00eas D.","family":"Costa","sequence":"additional","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), University of Porto, Rua Dr. Roberto Frias 400, 4200-465 Porto, Portugal"}]},{"given":"Eduardo A. S.","family":"Marques","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering (FEUP), University of Porto, Rua Dr. Roberto Frias 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1933-0865","authenticated-orcid":false,"given":"Ricardo J. C.","family":"Carbas","sequence":"additional","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), University of Porto, Rua Dr. Roberto Frias 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3272-4591","authenticated-orcid":false,"given":"Lucas F. M.","family":"da Silva","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering (FEUP), University of Porto, Rua Dr. Roberto Frias 400, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,24]]},"reference":[{"key":"ref_1","unstructured":"Moore, D.R., Pavan, A., and Williams, J.G. (2006). Fracture Mechanics Testing Methods for Polymers Adhesives and Composites, ESIS. ESIS Publication 28."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2133","DOI":"10.1080\/00218464.2021.1953479","article-title":"Testing mechanical performance of adhesively bonded composite joints in engineering applications: An overview","volume":"98","author":"Budzik","year":"2022","journal-title":"J. Adhes."},{"key":"ref_3","first-page":"1461","article-title":"Fracture energy assessment of adhesives\u2014Part I: Is GIC an adhesive property? 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