Investigating the Material Properties and Microstructural Changes of Fused Filament Fabricated PLA and Tough-PLA Parts

Abstract

Fused deposition modelling (FDM) is a popular but complex additive manufacturing process that works with many process parameters which are crucial to investigate. In this study, 3D parts were fabricated by placing each filament layer in opposite direction to the others; for this, two combinations of raster angles, (45° −45°) and (0° 90°), along with three different infill speeds were used. In this study, two 3D printing material types—Polylactic Acid (PLA) and tough-PLA were used. The material properties of each 3D part were investigated to identify the best combination of these parameters. A microstructural analysis was also performed on outer and inner surfaces along with fracture interface of the parts after tensile testing using a scanning-electron-microscopy (SEM) to explain material failure modes and reasons. The results suggest that for both the material types, a raster angle of 45° −45° produces stronger parts than to a raster angle of 0° 90°. This study also suggests that a slow infill speed improves tensile properties by providing a better inner-connection between two contiguous roasters. Thus, the detailed analysis of microstructural defects correlated with tensile test results provides insight into the optimisation of raster angle and infill speed, and scope for improvement of mechanical properties.

Influence of Infill Pattern on the Elastic Mechanical Properties of Fused Filament Fabrication (FFF) Parts through Experimental Tests and Numerical Analyses

“…This difference could produce a different ductile behavior among the Linear infill pattern specimens. Similar characteristics were found in [ 9 ]. On the other hand, all specimens (Linear090, Linear45, and Grid) with a Vertical orientation present a clear fracture surface and low elongation values.…”

“…The infill pattern and raster orientation have a significant impact on the mechanical properties of the FFF samples. Several studies [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] investigate the influence of these parameters on the properties of FFF printed materials, mainly PLA, but also ABS. The experimental test performed in almost all cases is the tensile test.…”

Influence of Infill Pattern on Mechanical Behavior of Polymeric and Composites Specimens Manufactured Using Fused Filament Fabrication Technology

“…Therefore, to characterize the mechanical behavior of an FFF part, it is essential to understand the effects that the FFF parameters have on the anisotropic material properties. Parameters such as the layer height, nozzle diameter, raster angle [ 31 , 32 ] or infill pattern [ 33 , 34 ] of the melted filaments [ 35 ], for both the pure polymer and fiber in a composite material, and infill density must be taken into account in the mechanical response of the specimen obtained using this process [ 5 , 7 , 8 , 22 , 36 , 37 ].…”

FFF 3D Printing in Electronic Applications: Dielectric and Thermal Properties of Selected Polymers

“…Materials based on polyvinyl chloride (PVC) are advanced, when considering their chemical resistance to oils, salts, and water [14]. To date, most studies on 3D printing have focused on the evaluation of mechanical properties [15,16], such as the tensile strength of materials based on ABS [17][18][19][20] and PLA [21][22][23] or their ability to resist pressure [24]. Additionally, the methods to increase their mechanical properties by annealing [25], using an auxiliary heating plate [26], choosing a suitable density and topology of infill [27][28][29], or adding metal particles [30] are examined.…”