PSI - Issue 56

Estera Vălean et al. / Procedia Structural Integrity 56 (2024) 58 – 64 Estera Vălean et al. / Structural Integrity Procedia 00 (2023) 000 – 000

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4

4. Results and discussion The experimental setup and the average stress - strain diagrams are shown in Fig. 2. Particularly, PLA specimens present a more brittle behavior with respect to PLA-CF. The mechanical properties are provided in Table 1.

Table 1. Average of the experimental results, for smooth specimens. Average PLA PLA-CF E [MPa] 3250.6 3203.3 [MPa] 41.59 33.48 [MPa] 2.28 4.32

5

F

5

1 15 2 25

tress M a

5

1

2

5

train

Fig. 2. a) Example showing one dog bone specimen that was tested under tensile loading and b) average stress -strain curves for PLA and PLA CF.

Fig. 3 reports the force - displacement curves for the notched specimens together with the critical load to failure vs. notch opening angle. It is worth highlighting that the unreinforced material over performed with respect to the reinforced one for both smooth and notch specimens. No clear trend can be observed with changing the notch opening angle; however, both materials present a minimum of the critical load to failure at 60º. The test results, in terms of load to failure, are summarized in Table 2.

Table 2. Summary of the experimental results, in terms of load to failure, for V ‐ notched specimens. PLA

PLA-CF

30°

60°

90°

120°

30°

60°

90°

120°

No. Sample

Fmax[N]

Fmax[N]

Fmax[N]

Fmax[N]

Fmax[N]

Fmax[N]

Fmax[N]

Fmax[N]

1 2 3 4 5

1513 1498 1483 1441 1560

1203 1217 1181 1228 1195

1288 1329 1279 1270 1386

1711 1691 1705 1742 1704

938 921 915 906 925

743 736 743 734 752

796 794 852 835 818

1049 1015 1062 1036 1063

Average

1499

1205

1310

1711

921

742

819

1045