Infill Strategy in 3D Printed PLA Carbon Composites: Effect on Tensile Performance

Abstract

Tuning the infill pattern is one of the key features in additive manufacturing to optimise part weight. In this work, the effect of the infill strategy, including rate and pattern type, is studied on the mechanical performance of polylactic acid (PLA)-carbon composite. In particular, three types of patterns and four filling levels are combined. These combinations are evaluated by tensile loading applied on dogbone specimens. In addition, the underlined deformation mechanisms are further explored using filament-based finite element model. The numerical simulation is built from sliced models and converted into 3D meshes to predict tensile performance. The results show that the infill rate has a nonlinear effect on the density of PLA–carbon composites, and its magnitude depends on the complexity of the generated pattern. In addition, tensile loading is found to activate varied modes of shearing and uniaxial deformations depending on the pattern type. This leads to different profiles and rankings of the tensile performance and allows the infill strategy to significantly affect the part performance, along with its density.

Process parameter tailored evaluation of FFF-fabricated carbon fibre based poly-lactic-acid composites

“…The CF-PLA specimen achieves a maximum TS of 27.62 MPa at LH 0.1 mm, FR 40 mm/s, and RA 0°, which is greater than the results reported by Jasim et al 47 (23.08 MPa), Özgül et al 48 (about 22 MPa), Guessasma and Belhabib 49 (about 17 MPa), and Ganeshkumar et al 50 (about 19 MPa) for pure PLA with gyroid infill pattern.…”

Influence of Process Parameters on the Characteristics of Additively Manufactured Parts Made from Advanced Biopolymers

“…There are several common filaments with carbon fiber filling, including PLA and polyethylene terephthalate glycol (PETG). Guessasma et al [ 167 ] investigated the use of different infill patterns to improve the tensile properties of printed carbon PLA structures. The samples were fabricated from PLA filaments reinforced with 10 wt % ground carbon fibers with a maximum particle size of 0.15 mm.…”

“…The results in Figure 27 show that the infill density affects the mechanical properties, although these dependencies vary for the different filling patterns due to the different compactness of the patterns [ 167 ]. The gyroid pattern is the best option for improving the mechanical strength, while zigzag and cross patterns are more suitable for promoting large strains, especially at low infill rates.…”

“… Three different tensile specimen patterns (zigzag, gyro, and cross) with 25% infill density [ 167 ]. …”

“… Correlations between engineering constants and the density of PLA–carbon fiber patterns with different infill densities ranging from 25% (point with lowest density) up to 100% at points with the highest material density [ 167 ]. …”