A Critical Analysis of Young's Modulus Determination for Fused Filament Fabricated Polylactic Acid Specimens

Andrej Cupar; Jasmin Kaljun

doi:https://doi.org/10.47960/3029-3200.2026.2.1.1

Research Article

DOI: https://doi.org/10.47960/3029-3200.2026.2.1.1

Andrej Cupar

and Jasmin Kaljun*

	andrej.cupar@um.si
*CA	jasmin.kaljun@um.si

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Vol. 2 No. 1 Article 13

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A. Cupar and J. Kaljun, “A Critical Analysis of Young’s Modulus Determination for Fused Filament Fabricated Polylactic Acid Specimens,” International Journal of Innovative Solutions in Engineering, vol. 2, no. 1, pp. 1–14, Jan. 2026, doi: 10.47960/3029-3200.2026.2.1.1.

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Abstract

This research investigates the influence of key Fused Filament Fabrication (FFF) process parameters on the tensile properties of Polylactic Acid (PLA). Dog-bone specimens, compliant with ISO 527-2, were printed in three distinct build orientations and at two extrusion temperatures. Uniaxial tensile tests were performed to determine the Ultimate Tensile Strength, Elongation at Break, and Young’s Modulus. The results demonstrate the significant anisotropic mechanical behaviour of FFF-printed PLA, with vertically oriented specimens exhibiting the highest strength. A critical analysis of methodologies for determining material stiffness was also conducted, comparing the standard ISO 527 Young’s Modulus against a Linear Regression approach and a novel dynamically calculated Young’s Modulus method that identifies the most stable elastic region. Findings reveal that the calculation method significantly impacts the resulting Young’s Modulus, with the standard chord method overestimating stiffness by up to 14% compared to the more robust data-driven approaches. This study underscores the critical importance of both process parameter control and the selection of an appropriate analysis methodology for the accurate mechanical characterization of additively manufactured components for engineering applications.

Keywords

Fused Filament Fabrication (FFF), Polylactic Acid (PLA), Young’s Modulus, Anisotropy, Tensile Testing, ISO 527

ijise ID

13

URI

https://ijise.ba/article/13/

Publication Date

Jan. 21, 2026

References

I. Gibson, D. Rosen, and B. Stucker, Additive manufacturing technologies: 3D printing, rapid prototyping, and direct digital manufacturing, second edition. 2015. doi: https://doi.org/10.1007/978-1-4939-2113-3.
N. Rašović, “Recommended Layer Thickness to the Powder-Based Additive Manufacturing Using Multi-Attribute Decision Support,” Int J Comput Integr Manuf, vol. 34, no. 5, pp. 455–469, May 2021, doi: https://doi.org/10.1080/0951192X.2021.1891574.
S. Farah, D. G. Anderson, and R. Langer, “Physical and mechanical properties of PLA, and their functions in widespread applications — A comprehensive review,” 2016. doi: https://doi.org/10.1016/j.addr.2016.06.012.
A. Rodríguez-Panes, J. Claver, and A. M. Camacho, “The influence of manufacturing parameters on the mechanical behaviour of PLA and ABS pieces manufactured by FDM: A comparative analysis,” Materials, vol. 11, no. 8, 2018, doi: https://doi.org/10.3390/ma11081333.
V. Slavković, B. Hanželič, V. Plesec, S. Milenković, and G. Harih, “Thermo-Mechanical Behavior and Strain Rate Sensitivity of 3D-Printed Polylactic Acid (PLA) below Glass Transition Temperature (Tg),” Polymers (Basel), vol. 16, no. 11, Jun. 2024, doi: https://doi.org/10.3390/POLYM16111526.
W. D. Callister and D. G. Rethwisch, Materials science and engineering: an introduction, 10th ed. Hoboken: Wiley, 2018.
S. H. Ahn, M. Montero, D. Odell, S. Roundy, and P. K. Wright, “Anisotropic material properties of fused deposition modeling ABS,” Rapid Prototyp J, vol. 8, no. 4, 2002, doi: https://doi.org/10.1108/13552540210441166.
Q. Sun, G. M. Rizvi, C. T. Bellehumeur, and P. Gu, “Effect of processing conditions on the bonding quality of FDM polymer filaments,” Rapid Prototyp J, vol. 14, no. 2, 2008, doi: https://doi.org/10.1108/13552540810862028.
A. K. Sood, R. K. Ohdar, and S. S. Mahapatra, “Parametric appraisal of mechanical property of fused deposition modelling processed parts,” Mater Des, vol. 31, no. 1, 2010, doi: https://doi.org/10.1016/j.matdes.2009.06.016.
D. Popescu, A. Zapciu, C. Amza, F. Baciu, and R. Marinescu, “FDM process parameters influence over the mechanical properties of polymer specimens: A review,” Polym Test, vol. 69, 2018, doi: https://doi.org/10.1016/j.polymertesting.2018.05.020.
A. Lanzotti, M. Grasso, G. Staiano, and M. Martorelli, “The impact of process parameters on mechanical properties of parts fabricated in PLA with an open-source 3-D printer,” Rapid Prototyp J, vol. 21, no. 5, 2015, doi: https://doi.org/10.1108/RPJ-09-2014-0135.
Y. Zhang and K. Chou, “A parametric study of part distortions in fused deposition modelling using three-dimensional finite element analysis,” Proc Inst Mech Eng B J Eng Manuf, vol. 222, no. 8, 2008, doi: https://doi.org/10.1243/09544054JEM990.
B. M. Tymrak, M. Kreiger, and J. M. Pearce, “Mechanical properties of components fabricated with open-source 3-D printers under realistic environmental conditions,” Mater Des, vol. 58, 2014, doi: https://doi.org/10.1016/j.matdes.2014.02.038.
C. Phillips, M. Kortschot, and F. Azhari, “Towards standardizing the preparation of test specimens made with material extrusion: Review of current techniques for tensile testing,” Addit Manuf, vol. 58, p. 103050, Oct. 2022, doi: https://doi.org/10.1016/J.ADDMA.2022.103050.
M. Mani, T. Murugaiyan, and V. Shanmugam, “Mechanical characterization and puncture resistance of 3D-printed PLA lattice structures,” Polym Eng Sci, vol. 64, no. 10, pp. 5006–5021, Oct. 2024, doi: https://doi.org/10.1002/PEN.26897.
M. Soldo, “A Newly Modeling Procedure For Different Morphological Distributions Of Unit Cells In Lattice Structure With Constant Relative Density,” International Journal of Innovative Solutions in Engineering, vol. 1, no. 1, pp. 25–32, Jan. 2025, doi: https://doi.org/10.47960/3029-3200.2025.1.1.25.
V. Plesec, J. Humar, P. Dobnik-Dubrovski, and G. Harih, “Numerical Analysis of a Transtibial Prosthesis Socket Using 3D-Printed Bio-Based PLA,” Materials (Basel), vol. 16, no. 5, Mar. 2023, doi: https://doi.org/10.3390/MA16051985.
R. Afshar, S. Jeanne, and B. E. Abali, “Nonlinear Material Modeling for Mechanical Characterization of 3-D Printed PLA Polymer With Different Infill Densities,” Applied Composite Materials, vol. 30, no. 3, pp. 987–1001, Jun. 2023, doi: https://doi.org/10.1007/s10443-023-10122-y.
ISO, “Plastics – Determination of tensile properties – Part 1: General principles,” 527-1, no. 527–1, 2019.
American Society for Testing and Materials, “ASTM D638-14,” ASTM International, vol. 82, no. C, 2016.
J. R. C. Dizon, A. H. Espera, Q. Chen, and R. C. Advincula, “Mechanical characterization of 3D-printed polymers,” 2018. doi: https://doi.org/10.1016/j.addma.2017.12.002.
I. Krešić, J. Kaljun, and N. Rašovć, “Controlling the Mechanical Response of Stochastic Lattice Structures Utilizing a Design Model Based on Predefined Topologic and Geometric Routines,” Applied Sciences 2024, Vol. 14, Page 6048, vol. 14, no. 14, p. 6048, Jul. 2024, doi: https://doi.org/10.3390/APP14146048.
ISO 37:2024(en), “Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties,” Browsing Platform (OBP). Accessed: May 21, 2024. [Online]. Available: https://www.iso.org/obp/ui/en/#iso:std:iso:37:ed-7:v1:en:fig:1