{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T20:25:19Z","timestamp":1792095919873,"version":"4.4.0"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T00:00:00Z","timestamp":1785974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Additive manufacturing has evolved beyond monomaterial fabrication, enabling the integration of dissimilar polymers within a single structure to achieve spatially tailored properties. In Fused Filament Fabrication (FFF), however, the discrete, layer-wise deposition and inherent material incompatibilities make the interfacial region a critical determinant of structural integrity. Rather than acting as a simple boundary, the interface governs stress transfer, damage initiation, and failure propagation, especially in biodegradable polymer systems where thermal and rheological mismatches are pronounced. This study investigates bi-component FFF structures manufactured from PLA and PLA\/PHA using mechanically interlocked interface geometries (T-type and dovetail configurations). Mechanical performance was assessed through tensile, flexural, and Charpy impact testing, complemented by fracture analysis, surface topography evaluation, and X-ray Computed Tomography (XCT) for internal defect characterization. The results establish correlations between interface design, defect distribution, and overall structural response.<\/jats:p>","DOI":"10.3390\/mi17080937","type":"journal-article","created":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T14:45:47Z","timestamp":1786027547000},"page":"937","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Interlocking Interfaces for Enhanced Mechanical Properties in Bi-Component 3D Printing of Biodegradable Materials"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-7656-1088","authenticated-orcid":false,"given":"Maria","family":"Catana (Oancea)","sequence":"first","affiliation":[{"name":"Department of Machine Manufacturing, Gheorghe Asachi Technical University of Iasi, Bd. Mangeron 59A, 700050 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-5850-6511","authenticated-orcid":false,"given":"Catalin","family":"Tampu","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Vasile Alecsandri University of Bacau, Calea M\u0103r\u0103\u015fe\u015fti 157, 600115 Bac\u0103u, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simona-Nicoleta","family":"Mazurchevici","sequence":"additional","affiliation":[{"name":"Department of Machine Manufacturing, Gheorghe Asachi Technical University of Iasi, Bd. 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Akademicka 2A, 44-100 Gliwice, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3764-4243","authenticated-orcid":false,"given":"Virgil Gabriel","family":"Teodor","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Dunarea de Jos University of Galati, Street Domneasc\u0103 nr. 111, 800201 Gala\u021bi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5890-3195","authenticated-orcid":false,"given":"Florin","family":"Susac","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Dunarea de Jos University of Galati, Street Domneasc\u0103 nr. 111, 800201 Gala\u021bi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica Silvia","family":"Tatarciuc","sequence":"additional","affiliation":[{"name":"\u201cGrigore T. Popa\u201d Faculty of Dental Medicine, University of Medicine and Pharmacy Iasi, Universit\u0103\u021bii Street 16, 700115 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6526-5622","authenticated-orcid":false,"given":"Panagiotis","family":"Kyratsis","sequence":"additional","affiliation":[{"name":"Department of Product and Systems Design Engineering, University of Western Macedonia, 50100 Kila Kozani, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ion","family":"Tiseanu","sequence":"additional","affiliation":[{"name":"National Institute of Laser Plasma and Radiation Physics, P.O. Box MG-36, 76900 Bucharest-Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1381-8963","authenticated-orcid":false,"given":"Cosmin","family":"Dobrea","sequence":"additional","affiliation":[{"name":"National Institute of Laser Plasma and Radiation Physics, P.O. Box MG-36, 76900 Bucharest-Magurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yujiao","family":"Ke","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7846-4102","authenticated-orcid":false,"given":"Viorel","family":"P\u0103unoiu","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Dunarea de Jos University of Galati, Street Domneasc\u0103 nr. 111, 800201 Gala\u021bi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6023-5544","authenticated-orcid":false,"given":"Dumitru","family":"Nedelcu","sequence":"additional","affiliation":[{"name":"Department of Machine Manufacturing, Gheorghe Asachi Technical University of Iasi, Bd. Mangeron 59A, 700050 Iasi, Romania"},{"name":"Technical Sciences Academy of Romania, Blvd. Dacia 26, 030167 Bucharest, Romania"},{"name":"Academy of Romanian Scientists, Ilfov Street 3, Sector 5, 050044 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Dey, A., Roan Eagle, I.N., and Yodo, N. (2021). A Review on Filament Materials for Fused Filament Fabrication. J. Manuf. Mater. Process., 5.","DOI":"10.3390\/jmmp5030069"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Fico, D., Rizzo, D., Casciaro, R., and Esposito Corcione, C. (2022). A Review of Polymer-Based Materials for Fused Filament Fabrication (FFF): Focus on Sustainability and Recycled Materials. 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