PSI - Issue 61

Artem Pepeliaev et al. / Procedia Structural Integrity 61 (2024) 224–231 Artem Pepeliaev / Structural Integrity Procedia 00 (2019) 000 – 000

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ABS+CF_0 ABS+CF_90 PA12+CF_0 PA12+CF_90 PET-G+GF_0 PET-G+GF_90 ABS+GF_0 ABS+GF_90

ABS+CF_0 ABS+CF_90 PA12+CF_0 PA12+CF_90 PET-G+GF_0 PET-G+GF_90 ABS+GF_0 ABS+GF_90 ABS+CF_0 ABS+CF_90 PA12+CF_0 PA12+CF_90 PET-G+GF_0 PET-G+GF_90 ABS+GF_0 ABS+GF_90

ABS+CF_0 ABS+CF_90 PA12+CF_0 PA12+CF_90 PET-G+GF_0 PET-G+GF_90 ABS+GF_0 ABS+GF_90

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012345678910 0

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(a) (b) Fig. 3 Stress-strain diagram for a series of filled polymer samples with different nozzles and angles: (a) 0.4 mm nozzle; (b) 0.8mm nozzle

For samples made of PA12, a significant reduction in plastic deformation was observed. Samples fabricated with infill angle of 90° exhibit plastic deformations, which may indicate that the fiber does not perform effectively with this orientation. These results highlight the importance of proper distribution and direction of reinforcing fibers to achieve optimal mechanical performance in reinforced composite materials. 3.3. Failure analysis The total work of the external force expended on the fracture of the sample is resilience, which can be measured by the area under the curve of the tensile diagram formed from experimental data points - stresses and strains. The entire area under the curve is divided into a finite number of geometric figures (trapezoids) which are formed from two pairs of experimental stress and relative strain data. To determine the discrete area of a trapezoid, the standard formula is used: ( ) 2 1 2 1 2     + − , (1) where i  and i  , for i = 1 it is the first point and for i = 2 it is the second point with the corresponding coordinates between which a rectangular trapezoid is enclosed. From the geometric point of view 1  and 2  is the length of the bases of the trapezoid, and the difference 2 1   − is the height of the trapezoid. In order to calculate the resulting value of the area under the curve, it is necessary to add up all the values of the discrete areas. This data is displayed in Table 4 for each type of the studied specimen.

Table 4. Resilience values for the studied samples

Nozzle

PA12

PET-G

ABS

0° 90°

0.4 mm

Pure

CF

Pure

GF

Pure

CF

GF

3337.88 ± 1526.38 596.35±309.49

286.50 ± 97.22 992.19±346.17

100.13±8.53 123.01±27.55

109.40±40.00 60.36±16.51

132.99±12.90 94.63±17.66

151.04±15.45 78.49±22.21

187.30±19.71

77.04±13.61 0.8 mm 0° 4232.21 ± 798.85 287.79 ± 51.20 207.14 ± 56.24 200.36 ± 40.25 233.41±56.67 283.22±49.66 338.84±56.69 90° 284.28±109.965 246.46±72.28 83.86±22.60 39.72±8.58 187.83±44.50 216.58±23.96 182.84±16.06