Comparative Study of Tensile Properties between Fused Filament Fabricated and Injection-Molded Wood-PLA Composite Parts

Abstract

The present study evaluates the manufacturing parameters effects on the tensile properties of material composed by polylactic acid (PLA) with wood fibers known as Timberfill. The specimens were built through fused filament fabrication (FFF). The influence of four printing parameters (Layer height, Fill density, Printing velocity, and Orientation) are considered through a L27 Taguchi orthogonal array in order to reduce experimental runs. Tensile test is applied to obtain the response variable used as output results to perform the ANOVA calculations. Fill density is the most influential parameter on the tensile strength, followed by building orientation and layer height, whereas the printing velocity shows no significant influence. The optimal set of parameters and levels is found, being 75% fill density, 0○Z-axis orientation, 0.4 mm layer height, and 40 mm/s velocity as the best combination. Applying this combination showed 9.37 MPa in maximum tension. Lastly, five solid Timberfill specimens manufactured via injection molding technology were also tested and the results compared to the printed samples. The values of the elastic modulus, elastic limit, and maximum tension of the injected samples were almost twofold of those were obtained for the FFF samples, but the maximum elongation of injected specimens was fell sharply.

Influence of the Manufacturing Method (3D Printing and Injection Molding) on Water Absorption and Mechanical and Thermal Properties of Polymer Composites Based on Poly(lactic acid)

“…The results of the mechanical tests fall in line with the results from similar work [ 2 , 3 , 4 , 5 ]. Research has shown an evident link between layer thickness and the mechanical properties of 3D-printed wood/PLA.…”

“…More pores mean less solid material, leading to a decrease in overall strength and modulus of the printed specimen. In simpler terms, the research has found that using thinner layers packs more material into the same volume, resulting in stronger and stiffer printed parts [ 2 , 3 , 4 , 5 ].…”

“…The mechanical properties of a 3D-printed component will depend on several printing and manufacturing parameters. Examples of such parameters include the raster angle, the infill percentage, the printing speed, the printing temperature, the bed temperature, and the printing layer thickness [ 4 ]. The printing layer thickness is a major influencing parameter because a smaller layer height provides improved bonding and adhesion between the layers, and this increase in contact area makes the cohesion stronger and stiffens the material [ 5 ].…”

Ποιοτική Διερεύνηση (Βελτιστοποίηση - Μοντελοποίηση) Παραμέτρων Της Τρισδιάστατης Εκτύπωσης Πολυμερών Υλικών Για Την Παραγωγή Λεπτότοιχων Φυσικών Πρωτοτύπων Με Εφαρμογή Στο Σχεδιασμό Και Την Κατασκευή Διακοσμητικών Αντικειμένων Εσωτερικού Χώρου

“…στην ακεραιότητα των κατασκευασμένων μερών αποτελεί ένα κρίσιμο θέμα για πολλούς ερευνητές[34,101,[128][129][130].Αξίζει να σημειωθεί ότι η έλλειψη επαρκούς προσκόλλησης μεταξύ των στρωμάτων του νήματος επηρεάζει αρνητικά την ποιότητα της επιφάνειας των μοντέλων και μπορεί να δημιουργήσει πόρους και ανεπιθύμητες ρωγμές[131][132][133]. Ο Wang[134] είχε αναφέρει ότι η επίδραση συμπίεσης του ακροφυσίου και της διάχυσης επηρεάζει τη μορφή της ποιότητας της επιφάνειας και ανέπτυξε ένα γεωμετρικό μοντέλο για την πρόβλεψη της επιφανειακής τραχύτητας για επίπεδες και κάθετες επιφάνειες.…”