PSI - Issue 31

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Procedia Structural Integrity 31 (2021) 111–115

4th International Conference on Structural Integrity and Durability, ICSID 2020 Digital light processing in photoelastic models production for material behavior modeling 4th International Conference on Structural Integrity and Durability, ICSID 2020 Digital light processing in photoelastic models production for material behavior modeling

M. Dundović a , K. Marković a, *, M. Franulović a , Ž. Vrcan a a University of Rijeka, Faculty of Engineering, Vukovarska 58, HR-51000 Rijeka, Croatia M. Dundović a , K. Marković a, *, M. Franulović a , Ž. Vrcan a a University of Rijeka, Faculty of Engineering, Vukovarska 58, HR-51000 Rijeka, Croatia

© 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID 2020 Organizers. © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID 2020 Organizers. Abstract Material behavior modeling for additive man fa turing (AM) te hnol gy represents a challenge because the manufacturi g proc ss and pos -processing parameters strongly influence the mech ical prop rties of the part. Photoelasticity is a well-known full-field optical technique used for di ect stress/strain determination and de ign evaluation purposes. A novel use of d git l light processing (DLP), a form of vat polymerization AM technologies n photoela tic specimen produ tion is discussed in this paper. A number of preliminary xperiments were undertaken to add ss critic l issues related t DLP process. It was concluded that the UV exposure time, depen ent ostly on lay r thickness, nd orientation are the main factors affec ing the mechanical properties and the ccuracy of the print samples. Pure bending test was used to de erm n mechanical and photoelastic pro ertie of a commercially avai ble acrylic-based photopolymer, not previously rep rted in the literat re. The rectangular b am s mple used was built in vertical yer orientation and fully-cured. The stimated value of Young’s modulus was within the expected range for acrylics, and the ph toelastic tant obtained provides increased confid nce in the investigated acrylic polymer for photoelastic stress analysis purposes, and consequently for validation of computer-based models. © 2021 The Authors. Published by ELSEVIER B.V. This is an ope acces article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID 2020 Organizers. Abstract Material behavior modeling for additive manufacturing (AM) technology represents a challenge because the manufacturing process and post-processing parameters strongly influence the mechanical properties of the part. Photoelasticity is a well-known full-field optical technique used for direct stress/strain determination and design evaluation purposes. A novel use of digital light processing (DLP), a form of vat polymerization AM technologies in photoelastic specimen production is discussed in this paper. A number of preliminary experiments were undertaken to address critical issues related to DLP process. It was concluded that the UV exposure time, dependent mostly on layer thickness, and orientation are the main factors affecting the mechanical properties and the accuracy of the printed samples. Pure bending test was used to determine mechanical and photoelastic properties of a commercially available acrylic-based photopolymer, not previously reported in the literature. The rectangular beam sample used was built in vertical layer orientation and fully-cured. The estimated value of Young’s modulus was within the expected range for acrylics, and the photoelastic constant obtained provides increased confidence in the investigated acrylic polymer for photoelastic stress analysis purposes, and consequently for validation of computer-based models.

Keywords: Photoelasticity, Digital Light Processing (DLP), pure bending test, material behavior modeling Keywords: Photoelasticity, Digital Light Processing (DLP), pure bending test, material behavior modeling

* Corresponding author. Tel.: +385 (0) 51 651 535 E-mail address: kristina.markovic@riteh.hr * Correspon ing author. Tel.: +385 (0) 51 651 535 E-mail address: kristina.markovic@riteh.hr

2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID 2020 Organizers. 2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an ope acces article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID 2020 Organizers.

2452-3216 © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID 2020 Organizers. 10.1016/j.prostr.2021.03.018