# The Impact of Internal Structure Changes on the Damping Properties of 3D-Printed Composite Material
## 6 Discussion  
These findings have significant implications for engineering applications involving composite materials. By understanding how the arrangement of internal reinforcement affects internal damping, engineers and designers can optimize the design and performance of composite structures. This knowledge can lead to the development of more efficient and reliable mechanical components and systems across various fields of engineering, from aerospace to the automotive industry. For example, when designing composite parts where both strength and high vibration-damping capability are important, it may not be  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Variant 2**} & \multicolumn{2}{c}{**Carbon Fiber**} & \multicolumn{2}{c}{**Fiberglass**} & \multicolumn{2}{c}{**Kevlar Fiber**} \\ \cline{2-7}  & **k [N/m]** & **E [GPa]** & **k [N/m]** & **E [GPa]** & **k [N/m]** & **E [GPa]** \\ \hline
0\({}^{\circ}\) & 4800 & 12.068 & 3169 & 7.967 & 3383 & 8.505 \\ \hline
45\({}^{\circ}\) & 2523 & 6.343 & 1728 & 4.344 & 1774 & 4.46 \\ \hline
90\({}^{\circ}\) & 2473 & 6.218 & 1637 & 4.116 & 1885 & 4.739 \\ \hline \(\pm\)45\({}^{\circ}\) & 2523 & 6.343 & 1587 & 3.99 & 1726 & 4.341 \\ \hline
0\({}^{\circ}\), 90\({}^{\circ}\) & 4332 & 10.891 & 2437 & 6.126 & 3274 & 8.232 \\ \hline \hline \end{tabular}
\end{table}
Table 6: Mechanical properties of variant 2.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Variant 1**} & \multicolumn{2}{c}{**Carbon Fiber**} & \multicolumn{2}{c}{**Fiberglass**} & \multicolumn{2}{c}{**Kevlar Fiber**} \\ \cline{2-7}  & **k [N/m]** & **E [GPa]** & **k [N/m]** & **E [GPa]** & **k [N/m]** & **E [GPa]** \\ \hline
0\({}^{\circ}\) & 4403 & 11.069 & 2656 & 6.677 & 4104 & 10.318 \\ \hline
45\({}^{\circ}\) & 1200 & 3.017 & 773 & 1.945 & 644 & 1.621 \\ \hline
90\({}^{\circ}\) & 1140 & 2.868 & 682 & 1.717 & 918 & 2.31 \\ \hline \(\pm\)45\({}^{\circ}\) & 1323 & 3.326 & 768 & 1.931 & 687 & 1.729 \\ \hline
0\({}^{\circ}\), 90\({}^{\circ}\) & 3888 & 9.775 & 2187 & 5.498 & 2497 & 6.278 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Mechanical properties of variant 1.  
suitable in some cases to use a 0\({}^{\circ}\),90\({}^{\circ}\) fiber orientation, since this configuration has lower damping capabilities. The study by [PERSON] (2023) indicates that such a structure has a higher probability of fiber damage under stress ([PERSON], 2024). A more suitable solution might be to use a fiber orientation of 90\({}^{\circ}\) or \(\pm\)45\({}^{\circ}\), where the probability of fiber damage is lower and the damping capability is significantly higher.  
To gain a deeper understanding of the impact of internal reinforcement arrangement on the internal damping of composite materials, it is essential to delve into the mechanisms that govern energy dissipation in the material. One of the critical factors to consider is the interphase bonding between the reinforcement fibers and the matrix material. The quality and strength of this bonding interface can significantly influence the material's ability to dissipate energy through internal damping mechanisms. Future research efforts could focus on elucidating the correlation between interphase bonding characteristics and the internal damping exhibited by composite materials with different reinforcement arrangements.  
Understanding how different reinforcement materials interact with the matrix and contribute to energy dissipation can pave the way for the development of composite materials with tailored damping properties suited to specific engineering applications. Therefore, it is essential to continue broadening the scope of research to include a diverse range of reinforcement materials. Investigating the internal damping behavior of composites reinforced with materials such as glass fibers, aramid fibers or even natural fibers like bamboo or jute could reveal unique damping properties, thereby enabling the advantages of composite materials to be utilized in new fields.