Determination of mechanical properties of very thin 3D-printed specimens for numerical analysis of tensile strength and fracture toughness

Authors

  • Petr Bočan Czech Technical University in Prague, Faculty of Civil Engineering, Department of Mechanics, Thákurova 7, 166 29 Prague, Czech Republic
  • Aleš Jíra Czech Technical University in Prague, Faculty of Civil Engineering, Department of Mechanics, Thákurova 7, 166 29 Prague, Czech Republic

DOI:

https://doi.org/10.14311/AP.2025.65.0263

Keywords:

fracture mechanics, simple tensile, numerical analysis, 3D printing, polyamide PA12

Abstract

This research deals with the influence of thickness on the mechanical properties of polyamide (PA12) samples produced by the SLS 3D technology. Experiments included fracture toughness and simple tensile tests on samples with thicknesses ranging from 0.50 mm to 2.00 mm. The experiment revealed that the thickness of the specimen significantly affected the tensile strength and Young’s modulus. The measured tensile strength (22–34 MPa) was notably lower than the 41 MPa reported by the manufacturer. As a result, a numerical analysis using ATENA software showed substantial discrepancies between the FEA predictions and the experimental data. This led to a modification of the material model and the determination of the effective Young’s modulus fit to thin polyamide samples, which improved the agreement of the numerical and experimental data.

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References

A. Cheng, A. Humayun, D. J. Cohen, et al. Additively manufactured 3D porous Ti-6Al-4V constructs mimic trabecular bone structure and regulate osteoblast proliferation, differentiation and local factor production in a porosity and surface roughness dependent manner. Biofabrication 6(4):045007, 2014. https://doi.org/10.1088/1758-5082/6/4/045007

Q. Ran, W. Yang, Y. Hu, et al. Osteogenesis of 3D printed porous Ti6Al4V implants with different pore sizes. Journal of the Mechanical Behavior of Biomedical Materials 84:1–11, 2018. https://doi.org/10.1016/j.jmbbm.2018.04.010

A. Jíra, M. Šejnoha, T. Krejčí, et al. Mechanical properties of porous structures for dental implants: Experimental study and computational homogenization. Materials 14(16):4592, 2021. https://doi.org/10.3390/ma14164592

L. Řehounek, A. Jíra, P. Hájková, Z. Čejka. Optimization of 3D printed trabecular structures for implantology and their mechanical analysis, 2017. Unpublished report from TAČR project No. TJ01000328.

A. H. Schoen. Infinite periodic minimal surfaces without self-intersections. Tech. Rep. TN D-5541, NASA, 1970.

P. Bočan. Experimental verification of the influence of thickness on 3D printed samples on fracture toughness parameters. Master’s thesis, Czech Technical University in Prague, 2024. [2024-08-10]. http://hdl.handle.net/10467/113955

A. Jíra, L. Řehounek, G. Javorská, P. Padevěd. Experimental investigation of defects of thin 3D-printed plates. In 60th Annual Conference on Experimental Stress Analysis, pp. 1–5. 2022.

M. Varghese, M. W. Grinstaff. Beyond nylon 6: Polyamides via ring opening polymerization of designer lactam monomers for biomedical applications. Chemical Society Reviews 51(19):8258–8275, 2022. https://doi.org/10.1039/D1CS00930C

S. Shiva, R. G. Asuwin Prabu, B. Gauri, et al. A review on the recent applications of synthetic biopolymers in 3D printing for biomedical applications. Journal of Materials Science: Materials in Medicine 34(12):62, 2023. https://doi.org/10.1007/s10856-023-06765-9

M. Shakiba, E. Rezvani Ghomi, F. Khosravi, et al. Nylon – A material introduction and overview for biomedical applications. Polymers for advanced technologies 32(9):3368–3383, 2021. https://doi.org/10.1002/pat.5372

H. Kim, S. Jeong. Case study: Hybrid model for the customized wrist orthosis using 3D printing. Journal of mechanical science and technology 29(12):5151–5156, 2015. https://doi.org/10.1007/s12206-015-1115-9

O. A. Alo, D. Mauchline, I. O. Otunniyi. 3D-printed functional polymers and nanocomposites: Defects characterization and product quality improvement. Advanced Engineering Materials 24(5):2101219, 2022. https://doi.org/10.1002/adem.202101219

S. Wickramasinghe, T. Do, P. Tran. FDM-based 3D printing of polymer and associated composite: A review on mechanical properties, defects and treatments. Polymers 12(7):1529, 2020. https://doi.org/10.3390/polym12071529

A. G. Rodríguez, E. E. Mora, M. A. Velasco, C. A. N. Tovar. Mechanical properties of polyamide 12 manufactured by means of SLS: Influence of wall thickness and build direction. Materials Research Express 10(10):105304, 2023. https://doi.org/10.1088/2053-1591/acf6f7

D. Tasch, A. Mad, R. Stadlbauer, M. Schagerl. Thickness dependency of mechanical properties of laser-sintered polyamide lightweight structures. Additive Manufacturing 23:25–33, 2018. https://doi.org/10.1016/j.addma.2018.06.018

S.-L. Sindinger, C. Kralovec, D. Tasch, M. Schagerl. Thickness dependent anisotropy of mechanical properties and inhomogeneous porosity characteristics in laser-sintered polyamide 12 specimens. Additive Manufacturing 33:101141, 2020. https://doi.org/10.1016/j.addma.2020.101141

S. Aslanzadeh, H. Saghlatoon, M. M. Honari, et al. Investigation on electrical and mechanical properties of 3D printed nylon 6 for RF/microwave electronics applications. Additive Manufacturing 21:69–75, 2018. https://doi.org/10.1016/j.addma.2018.02.016

K. S. Randhawa, A. D. Patel. Influence of boric anhydride reinforcement on mechanical properties and abrasive wear of nylon 6. Materials Research Express 7(5):055303, 2020. https://doi.org/10.1088/2053-1591/ab8ee4

X. Wang, M. Jiang, Z. Zhou, et al. 3D printing of polymer matrix composites: A review and prospective. Composites Part B: Engineering 110:442–458, 2017. https://doi.org/10.1016/j.compositesb.2016.11.034

J. Červenka, L. Jendele, V. Červenka. ATENA program documentation. Tech. rep., Cervenka Consulting, 2014.

Sinterir sp. z o.o. PA12 Smooth – Material’s Technical Data Sheet, 2022.

K. S. Randhawa, A. D. Patel. A review on tribo-mechanical properties of micro-and nanoparticulate-filled nylon composites. Journal of Polymer Engineering 41(5):339–355, 2021. https://doi.org/10.1515/polyeng-2020-0302

M. Shakiba, E. Rezvani Ghomi, F. Khosravi, et al. Nylon – A material introduction and overview for biomedical applications. Polymers for advanced technologies 32(9):3368–3383, 2021. https://doi.org/10.1002/pat.5372

L. Ladani, M. Sadeghilaridjani. Review of powder bed fusion additive manufacturing for metals. Metals 11(9):1391, 2021. https://doi.org/10.3390/met11091391

International Organization for Standardization. EN ISO 12737. Metallic materials – Determination of plane-strain fracture toughness, 2010.

International Organization for Standardization. EN ISO 527-1. Plastics – Determination of tensile properties – Part 1: General principles, 2019.

International Organization for Standardization. EN ISO 527-2. Plastics – Determination of tensile properties – Part 2: Test conditions for moulding and extrusion plastics, 2012.

S. Akram, Q. U. Ann. Newton Raphson method. International Journal of Scientific & Engineering Research 6(7):1748–1752, 2015.

S. Antoniou, R. Pinho. Engineering Dynamics and Vibrations, chap. Nonlinear Seismic Analysis of Framed Structures: Recent Developments, pp. 268–301. CRC Press, 2018. https://doi.org/10.1201/9781315119908-8

A. Salazar, A. J. Cano, J. Rodríguez. Mechanical and fatigue behaviour of polyamide 12 processed via injection moulding and selective laser sintering. Analysis based on Kitagawa-Takahashi diagrams. Engineering Fracture Mechanics 275:108825, 2022. https://doi.org/10.1016/j.engfracmech.2022.108825

A. J. Cano, A. Salazar, J. Rodríguez. Effect of temperature on the fracture behavior of polyamide 12 and glass-filled polyamide 12 processed by selective laser sintering. Engineering Fracture Mechanics 203:66–80, 2018. https://doi.org/10.1016/j.engfracmech.2018.07.035

N. Lammens, M. Kersemans, I. De Baere, W. Van Paepegem. On the visco-elasto-plastic response of additively manufactured polyamide-12 (PA-12) through selective laser sintering. Polymer Testing 57:149–155, 2017. https://doi.org/10.1016/j.polymertesting.2016.11.032

L. Cobian, M. Rueda-Ruiz, J. P. Fernandez-Blazquez, et al. Micromechanical characterization of the material response in a PA12-SLS fabricated lattice structure and its correlation with bulk behavior. Polymer Testing 110:107556, 2022. https://doi.org/10.1016/j.polymertesting.2022.107556

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Published

2025-07-09

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How to Cite

Bočan, P., & Jíra, A. (2025). Determination of mechanical properties of very thin 3D-printed specimens for numerical analysis of tensile strength and fracture toughness. Acta Polytechnica, 65(3), 263–275. https://doi.org/10.14311/AP.2025.65.0263