Fabrication and response testing of a hybrid cellular structure with the ability to transform cells formed into diamond-shaped silhouettes

Tomažinčič, Dejan (author), Kajbič, Jure (author), Klemenc, Jernej (author)

The development, production and application of an active hybrid cell structure are presented. The composite structure is built from two very different materials, the combination of which enables changing the external geometry of the product with a temperature variation. The base (matrix) is a biodegradable polymer produced using additive manufacturing, to which wires made of high-strength material with a shape memory effect are subsequently added. The two materials are built into specially designed cell shapes with progressively increasing cell sizes. Since the wires are made of NiTinol alloy, this enables temperature activation of the wire network, which triggers controlled changes of the structure’s geometry. For this purpose, three implementations of cell structures were made with an objective to find the most effective backward transformation of the cellular structure after the activation of the wires. The activation of the structure was tested both in hot air and in hot water. Numerical simulations confirmed experimental tests and showed the strong regeneration ability of the hybrid especially in the third version of the structure.

• Language: English
• Keywords: additive manufacturing, PLA, NiTinol, shape memory effect, temperature activation, FEM numerical simulation
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 17 str.
• Numbering: Vol. 259, art. 114822
• PID: 20.500.12556/RUL-175242
• UDC: 620.1:519.876.5
• ISSN on article: 0264-1275
• DOI: 10.1016/j.matdes.2025.114822
• COBISS.SI-ID: 254349571
• Publication date in RUL: 22.10.2025

Record is a part of a journal

• Title: Materials & design
• Shortened title: Mater. des.
• Publisher: Scientific and Technical Press
• ISSN: 0264-1275
• COBISS.SI-ID: 10626075

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian

Abstract

Predstavljeni so razvoj, izdelava in možnosti uporabe aktivne hibridne celične strukture, zgrajena iz dveh povsem različnih materialov, ki v sodelovanju omogočata spremembo zunanje geometrije produkta. Osnova (matrica) je biorazgradljivi 3D tiskani polimer v katerega so naknadno vstavljene žice iz visoko-trdnostnega materiala z oblikovnim spominom SMA. Vse skupaj je načrtno povezano v posebne celične oblike, ki tvorijo površinsko progresivno naraščajočo strukturo vzorcev. Ker so žice izdelane iz zlitine NiTinol-a, to posledično omogoča temperaturno aktivacijo mreže mimobežno postavljenih žic, kar se odraža v možnosti kontroliranega spreminjanja geometrije strukture. V ta namen so bile izdelane tri izvedbe celičnih struktur s ciljem čim bolj efektivnega odziva geometrije celic matrice po aktivaciji žic. Aktivacija strukture je bila preizkušena tako na vročem zraku kot tudi v vroči vodi. Numerične simulacije in nato potrjeni eksperimentalni testi kažejo, zlasti pri tretji različici, na izrazito regeneracijsko sposobnost hibrida.

• Keywords: aditivna proizvodnja, oblikovni spomin materiala, temperaturna aktivacija, numerična simulacija MKE

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: Z2-50081
• Name: Razvoj celičnega kompozita s sposobnostjo transformacije celic z izbranim aktivacijskim mehanizmom