PSI - Issue 68

Estera Vălean et al. / Procedia Structural Integrity 68 (2025) 955 – 961 Vălean et al./ Structural Integrity Procedia 00 (2025) 000–000

958 4

100 120

0 100 200 300 400 500 600

PLA PLA-CF PLA-notch PLA_CF-notch

(a)

PLA PLA+CF

0 20 40 60 80

Force [N]

(b)

(a)

Flexural Stress [MPa]

0

0,05 0,1 0,15

0 2 4 6 8 10

(a)

Flexural Strain [mm/mm]

Displacement [mm]

Fig. 2. Flexural force-displacement (a) and flexural stress - flexural strain (b) curves of printed samples

From Figure 3a it can be seen that the virgin material has higher strength and fracture properties than the reinforced material for both smooth and notched specimens. Thus, the maximum strength difference between PLA and PLA-CF is 24%, and between PLA-notch and PLA-CF-notch is approximately 27%. If we look at the effect of the notch on the maximum strength, for the virgin material it is 22%, and for the reinforced material 25%. Due to the pronounced plastic deformation, reinforced PLA samples absorb the largest amount of energy (Figure 3b). The PLA samples are identified at the opposite pole. It is interesting that the total breaking energy has approximately equal values for the 2 types of material with notched specimens 0.45 J, respectively 0.46 J.

Fig. 3. The variation of stress (a) and energy (b) properties with the type of sample