{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T21:04:41Z","timestamp":1792011881087,"version":"4.4.0"},"reference-count":23,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100018987","name":"Ministry of Research, Innovation and Digitization","doi-asserted-by":"crossref","award":["31N\/2023"],"award-info":[{"award-number":["31N\/2023"]}],"id":[{"id":"10.13039\/100018987","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Valued for their lightweight, high strength-to-weight ratio, and energy absorption, sandwich composites were adopted across multiple industries. This paper evaluates the static and dynamic mechanical performances of sandwich configurations exploiting carbon fiber-reinforced polymer (CFRP) and quartz fiber-reinforced polymer (QFRP) composite skins bonded to hexagonal Nomex\u00ae or compliant Flex-Core\u00ae cores. Skin thickness varied negligibly; therefore, this study focused on skin type and particularly core architecture influence on mechanical behavior. Three-point bending and flatwise compression tests evaluated flexural stiffness, core shear strength, and core compressive strength. DMA analysis was used to characterize their temperature-dependent viscoelastic response through the storage modulus, loss modulus, and damping factor. QFRP\/Nomex emerged as the optimal configuration achieving the highest flexural stress, outperforming CFRP\/Nomex by 14%, while restricting strain to 2.4% (compared to 7% for CFRP). DMA (Dynamic Mechanical Analyzer) analysis showed that QFRP\/Nomex exhibits the highest storage and loss moduli. Observing the energy at break, CFRP\/Nomex\u00ae sandwiches stand out in their ability to absorb 60% more energy than QFRP\/Nomex\u00ae before total failure occurs, showing an overall superior energy absorption of CFRP skins. Conversely, flatwise compression tests revealed that QFRP\/Flex-Core\u00ae excelled in yield and compressive strengths, outperforming CFRP\/Nomex by 10% and 8%, respectively, due to superior elastic matching. DMA damping profiles confirmed that the geometric compliance of curved Flex-Core\u00ae cell walls in conjunction with QFRP skins accelerates structural yielding under shear and viscoelastic energy dissipation prior to chemical softening. This work highlights that sandwich structure design critically depends on managing core architecture and skin-to-core stiffness mismatch.<\/jats:p>","DOI":"10.3390\/polym18172090","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T18:33:52Z","timestamp":1787942032000},"page":"2090","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Influence of Skin\u2013Core Stiffness Mismatch on the Static and Dynamic Mechanical Performance of CFRP- and QFRP-Skinned Aramid Honeycomb Sandwich Structures"],"prefix":"10.3390","volume":"18","author":[{"given":"Madalina Andreea","family":"Mustareata","sequence":"first","affiliation":[{"name":"Composite Materials Laboratory for Aeronautical Field, Romanian Research and Development Institute for Gas Turbines\u2014COMOTI, 220D Iuliu Maniu Av., 061126 Bucharest, 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Standard Test Method for Core Shear Properties of Sandwich Constructions by Beam Flexure (Standard No. ASTM C393\/C393M-20)."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/17\/2090\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T04:26:54Z","timestamp":1788064014000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/17\/2090"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,28]]},"references-count":23,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["polym18172090"],"URL":"https:\/\/doi.org\/10.3390\/polym18172090","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,28]]}}}