PSI - Issue 68

J.M. Parente et al. / Procedia Structural Integrity 68 (2025) 160–165 J.M. Parente et al. / Structural Integrity Procedia 00 (2025) 000–000

162

3

3. Results Fig. 1 shows the three-point bending results for the nanocomposites filled with GNP. The bending stress and stiffness were maximized for 0.75 wt. % GNP, with values of 120.7 MPa and 3.54 GPa, respectively, which represent an increase of 10.8% and 11.7% over those obtained with the neat resin (108.96 MPa and 3.17 GPa, respectively). Regarding the bending strain, the highest amount of GNP (1 wt.%) led to the lowest value (4.11%), which is 19.22% lower than the control sample (5.0%). These values are in line with the data provided in the supplier's technical data sheets and are comparable to those reported by Parente et al. (2024).

)G+,-.,/)M12+PP)45S78 )G+,-.,/)M1.99,+PP)4:S78 )G+,-.,/)M127.,)4;8

<"!

&$!

$"!

$"$

("$

$"!

&(!

("$

("!

("!

&'!

'"$

'"$

&#!

'"!

'"!

#"$

!"#$B#&'()G/B#',PM

!"#$B#&'()G"++',-./M

!"#$B#&'()B44#"++',N./M #"!

&&!

#"$

&"$

&!!

#"!

&"!

!"!!

!"#$

!"$!

!"B$

&"!!

N2.',PM

Fig. 1. Effect of the GNP quantity on the flexural performance of the epoxy nanocomposite.

Fig. 2 shows the results obtained for the hybrid nanocomposites, where the bending stress and stiffness were maximized with values of 124.46 MPa and 3.709 GPa, respectively, for 0.25 wt.% of CNT and 0.5 wt.% of GNP. These values represent an improvement of 14.2% and 17.0% compared to the control sample. Regarding the bending stress the results were maximized, for 0.25 wt.% of CNT and 0.5 wt.% of GNP. These values represent a 20% improvement. Regarding the bending strain (Fig. 2c), the sample containing 0.375 wt.% of both nano-reinforcements exhibited the lowest value at around 4.7%. The results show that using a combined mixture of GNP and CNT can provide improved mechanical properties compared to using a single type of nanoparticle. The best results for GNP only and CNT-only nanocomposites showed a decrease of 3.1% and 8.1%, respectively, compared to the best hybrid results for bending strength. These results are in line with those documented by other authors (Bhandari et al., 2021; Wang et al., 2020).

Fig. 2. Effect of the nano-reinforcement hybridization on a) bending strength; b) bending stiffness, c) bending strain.