PSI - Issue 37

P.N.B. Reis et al. / Procedia Structural Integrity 37 (2022) 934–940

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P.N.B. Reis et al. / Structural Integrity Procedia 00 (2021) 000 – 000

the primary and secondary stage. This is a typical behaviour of creep curves, where the third stage is only expected for higher stress values or longer times. In this case, as expected, the tensile mode showed the highest stress relaxation, while the bending and compressive modes shows creep values vary close after 180 min. In fact, the small difference around 4% can be masked by the observed dispersion. These results prove that, independently of the loading mode, the creep phenomenon in polymers occurs even at room temperature which is explained by the molecular motion in backbone polymer arrangement. 4. Conclusions Different techniques have been explored, but fused filament fabrication (FFF) is the most widely used additive manufacturing process. However, due to the low mechanical properties of 3D printed parts, the emergence of polymeric nanocomposites with the objective of improving the properties of host matrices is not surprising. In this context, the present study aimed to analyse the stress relaxation and creep behaviour of a hybrid nanocomposite in compression, tensile and bending modes. It was possible to conclude that the bending mode had the lowest stress relaxation, while the highest was observed for the tensile mode. In terms of creep, the tensile mode had the highest displacement, while the bending and compression mode had very similar values. 5. Acknowledgements This research received external funding from the SAICT project n° 31296 “COMP4UAVs” supported by POCI in its FEDER component and by FCT-IP. This research was also sponsored by national funds through FCT - Fundação para a Ciência e a Tecnologia, under the project UIDB/00285/2020. 6. References Campbell, T. A., and Ivanova, O. S, 2013. 3D Printing of Multifunctional Nanocomposites. Nano Today 8, 2, 119 – 20. Daver, F., Kajtaz, M., Brandt, M., and Shanks, R. A., 2016. Creep and Recovery Behaviour of Polyolefin-Rubber Nanocomposites Developed for Additive Manufacturing. Polymers, 8, 12, 437. Dul, S., Fambri, L., Pegoretti, A., 2016. Fused Deposition Modelling with ABS-Graphene Nanocomposites. Composites Part A: Applied Science and Manufacturing, 85, March, 181 – 91. Ivanova, O., Williams, C., Campbell, T., 2013. Additive Manufacturing (AM) and Nanotechnology: Promises and Challenges. Rapid Prototyping Journal, 19, 5, 353 – 64. Kuang, X., Mu, Q., Roach, D. J., Qi, H. J., 2020. Shape-Programmable and Healable Materials and Devices Using Thermo- And Photo-Responsive Vitrimer. Multifunctional Materials, 3, 4, 045001. Love, L. J., Kunc, V., Rios, O., Duty, C. E., Elliott, A. M., Post, B. K, Smith, R. J., Blue, C. A., 2014. The Importance of Carbon Fiber to Polymer Additive Manufacturing. Journal of Materials Research, 29, 17, 1893 – 98. Mohamed, O. A., Masood, S. H., Bhowmik, J. L., 2016. Investigation on the Flexural Creep Stiffness Behavior of PC – ABS Material Processed by Fused Deposition Modeling Using Response Surface Definitive Screening Design. JOM, 69, 3, 498 – 505. Mohamed, O. A., Masood, S. H., Bhowmik, J. L., 2017. Experimental Investigation of Creep Deformation of Part Processed by Fused Deposition Modeling Using Definitive Screening Design. Additive Manufacturing, 18, 164 – 70. Mohammadizadeh, M., Fidan, I., Allen, M., Imeri, A., 2018. Creep Behavior Analysis of Additively Manufactured Fiber-Reinforced Components. International Journal of Advanced Manufacturing Technology, 99, 5 – 8, 1225 – 34. Mohammadizadeh, M., Imeri, A., Fidan, I., Elkelany, M., 2019. 3D Printed Fiber Reinforced Polymer Composites - Structural Analysis. Composites Part B: Engineering, 175, July, 107112. Niaza, K. V., Senatov, F. S., Stepashkin, A., Anisimova, N. Y., Kiselevsky, M. V., 2017. Long-Term Creep and Impact Strength of Biocompatible 3D-Printed PLA-Based Scaffolds. Nano Hybrids and Composites, 13, 15 – 20. Rashid, A. A., Koҫ, M., 2021. Creep and Recovery Behavior of Continuous Fiber-Reinforced 3dp Composites. Polymers, 13, 10, 1644. Salazar-Martín, A. G., Pérez, M. A., García-Granada, A. A., Reyes, G., Puigoriol-Forcada, J. M., 2018. A Study of Creep in Polycarbonate Fused Deposition Modelling Parts. Materials and Design, 141, 414 – 25. Seifans, A. M., Ayyagari, S., Al-Haik, M., 2021. Elastic/Viscoplastic Characterization of AdditivelyManufactured Composite Based on Continuous