Effect of different parameters on the tensile properties of printed Polylactic acid samples by FDM: experimental design tested with MDs simulation

Abstract

Fused Depositional Modeling (FDM) is one of the common methods for 3D printing of polymers, which is expanding in various industrial applications, scienti c researches, and engineering applications due to its ability to make complex parts. In this research, molecular dynamics (MDs) simulation has been used to predict the physical and mechanical properties. Then, the mechanical properties of the printed parts are obtained. The mechanical properties of 3D printed parts strongly depend on the correct selection of processing parameters. In this study, the effect of three important parameters such as in ll density, printing speed, and layer thickness are investigated on the tensile properties of PLA specimens. For this purpose, standard specimens with four in ll densities of 20%, 40%, 60% and 80%, two speeds of 20 mm/s, and 40 mm/s, and two thicknesses of 0.1 mm and 0.2 mm are printed and tested under quasistatic tensile test. In all printed specimens, the print angle is ± 45°. The experimental results show that the in ll density in comparison to the other two parameters has signi cant effect on mechanical properties such as modulus of elasticity, ultimate strength, and failure strain. According to these results, by increasing the in ll density, the stiffness and strength of the specimens increases considerably. At in ll density of 80%, the specimens has the highest stiffness and strength, but it exhibits a brittle behavior. Moreover, it can be deduced that by reducing the layer thickness although the modulus of elasticity increases a little, ductility is greatly affected.

The Influence of the Process Parameters on the Mechanical Properties of PLA Specimens Produced by Fused Filament Fabrication—A Review

“…The selection of the infill pattern and density must be correlated with the stress and strain states for the future product. Both parameters are major factors of influence on the mechanical properties of 3D FFF-printed components [ 22 , 23 , 24 , 25 ]. The infill characteristics are to be set into the slicer software (addressed in the next step), but it is important to highlight that the infill selection is part of the design process of the component.…”

The influence of fused filament fabrication printing parameters on the mechanical properties of a thermoplastic elastomer

“…However, increases in strength have not been observed unanimously, as another study in ABS showed decrease in tensile strength when PS was increased from 10 to 50 mm/s (Abbott et al, 2018). A similar effect was seen in PLA over a range of 30-60 mm/s (Yu et al, 2019) and at 20 and 40 mm/s (Farazin and Mohammadimehr, 2021), where higher speeds decreased strength. It is possible that the discrepancy in results is because of the range of PSs being tested.…”

Application of composite material models to determine the Young’s modulus of the grid pattern of partially infilled 3D printed samples

“…Likewise, Abeykoon et al found the highest modulus for the linear pattern with respect to diamond, moroccanstar, catfill, sharkfill, hexagonal and Hilbert, due to the smaller spaces between the individual layers [9]. Considering the infill percentage, the highest Young's modulus has been reported for samples with a 100% infill percentage [1,4,9,15,16]. However, a lower infill percentage decrease the amount of material required and the printing time, which decreases the cost of printing [1,15].…”