## 3 Results and Discussions  
### Bending Properties  
The three-point bending load-displacement curve of the samples with different hybrid ratios are shown in Figure 2. According to the load-displacement curve of the three-point bending of the sample in Figure 2, it can be seen that the tensile process of the sample node is divided into three stages, namely, the elastic stage, the plastic stage, and the sudden change stage of the strength peak. When the indenter begins to contact the specimen, the specimen begins to bear the load; at this time, it is in the elastic stage, and the specimen does not appear to have any damage. With the increase in load, the specimen enters the plastic stage, cracks begin to appear on the surface of the sample, and the sample begins to show irreversible damage, as shown in Figure 2a. When the applied load reaches the peak value, the load carried by the sample drops sharply, and the sample fails under severe damage (Figure 2a). Because of the existence of the honeycomb core, the sample still has a certain carrying capacity after the load redistribution, which is shown in Figure 2b,c.  
Figure 1: Sample diagram and hybrid scheme: (**a**) sample diagram; (**b**) hybrid scheme.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Sample** & **Layer** & **Hybrid Ratio** \\ \hline Sample-1(S-1) & G\({}_{6}\) & 0 \\ \hline Sample-2(S-2) & CG\({}_{4}\)C & 0.33 \\ \hline Sample-3(S-3) & C\({}_{2}\)G\({}_{2}\)C\({}_{2}\) & 0.67 \\ \hline Sample-4(S-4) & C\({}_{6}\) & 1 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Hybrid ratio and stacking sequence.  
As demonstrated in Figure 3a,d, the progressive addition of carbon fibers significantly enhances the flexural performance of hybrid composites. When the carbon/glass fiber hybrid ratio increases incrementally from 0 to 1, the longitudinal (L) direction (Figure 3a) exhibits peak load improvements of 16.21% (S-2), 26.54% (S-3), and 19.88% (S-4), accompanied by energy absorption (EA) enhancements (Figure 3b) from 11.62 J (S-1) to 14.20 J (S-2), 17.18 J (S-3), and 15.49 J (S-4), corresponding to increases of 22.20%, 47.85%, and 33.30%, respectively. The specific energy absorption (SEA) in the L direction (Figure 3c) rises from 0.17 J/g (S-1) to 0.21 J/g (S-2), 0.25 J/g (S-3), and 0.24 J/g (S-4), representing 23.53%, 47.06%, and 41.18% improvements. In the transverse (W) direction (Figure 3d), peak load increases by 30.99% (S-2), 34.38% (S-3), and 17.27% (S-4), while EA elevates (Figure 3e) from 11.77 J (S-1) to 12.63 J (S-2), 14.58 J (S-3), and 13.78 J (S-4), with percentage gains of 7.31%, 23.87%, and 17.08%. The SEA for the W direction (Figure 3f) progresses from 0.16 J/g (S-1) to 0.18 J/g (S-2), 0.21 J/g (S-3), and 0.20 J/g (S-4), showing increments of 12.50%, 31.25%, and 25.00%. By comparing the bending properties of the samples in different directions, it can be observed that as the hybrid ratio increases, the high strength of carbon fiber becomes more dominant during the bending process, resulting in a significant improvement in the bending properties of the sample. When the carbon fiber content in the sample reaches the limit, the toughness of the sample decreases due to the high carbon fiber content, and thus, the bending property of the sample decreases. Therefore, with the increase in the hybrid ratio, the overall performance shows a rise-then-decline trend. The adjacent units of the aluminum honeycomb core are connected by the adhesive mode and are more prone to failure under external load. When testing the W bending property of the sample, the bonding part between the adjacent core of the honeycomb is more prone to failure than the honeycomb wall under load. So, the bending properties of the sample in the L direction are greater than that in the W direction.  
Figure 2: The three-point bending load–displacement curve of samples with different hybrid ratios: (**a**) sample damage in the bending process; (**b**) bending load–displacement curve in the L direction; (**c**) bending load–displacement curve in the W direction.