PSI - Issue 51

M. Vaško et al. / Procedia Structural Integrity 51 (2023) 173–178 M. Vaško et al. / Structural Integrity Procedia 00 (2022) 000–000

175

3

The matrix component of the composite material was made up of nylon reinforced with chopped carbon fibre (trademark ONYX). The reinforcement used in the laminate was HSHT glass fibre. The data defined by the printer manufacturer indicate the mechanical properties shown in Table 1 (Markforged (2022)).

Table 1. Mechanical properties. Parameter Tensile modulus of elasticity [GPa]

Nylon Reinforced with Chopped Carbon Fibre (Onyx)

HSHT Glass fibre

1.4

21

Ultimate strength [MPa] Tensile strain at brake [%] Flexural strength [MPa]

30 58 50

600

3.9

420

The authors modified the printing parameters in the preparation process (see Table 2). Each laminate comprised 100 layers, whereas the thickness of laminas was 0.1 mm. The infill type was a solid fill with an infill density of 100 %.

Table 2. Printing parameters Parameter

Value

Layer thickness [mm] Base plane of specimen

0.1 XY

Matrix filament orientation in lamina [degrees]

45/-45

Fill density [%]

100

Reinforcement orientation

Unidirectional

Loading direction

Direct or perpendicular

The final laminate structure was a sandwich with a suitable fibre location concerning the presence of a notch and the need for comparability of results. The configuration of the reinforced laminas in the laminate was uniform concerning the ratio of the reinforced layers to the total number of laminas. The arrangement of the reinforced fibre in the laminas was unidirectional. Since directional dependence was shown during experimental tests of the investigated material (Vaško et al. (2020)), the direction of the loading force was oriented:  direct to stacking of laminas (Fig 2a),  perpendicular to stacking of laminas (Fig. 2b).

(a)

(b)

Fig. 2. Loading direction: (a) direct to laminas stacking; (b) perpendicular to laminas stacking.