## 2 Materials and Methods
### Quasi-Static Compression Experiments  
In order to study the influence of vertical load on the deformation mechanism and mechanical properties of the TPMS porous structure, the digital models (STL files) were processed in Matlab(r) v2021 software. Then, Materialise Magics(r) v24.0 was used to realize the array of the TPMS porous structure in the three coordinate directions of X, Y, and Z and obtain eight TPMS porous structure compression samples of 20 mm \(\times\) 20 mm \(\times\) 20 mm. SLM is one of the most common metal additive manufacturing technologies and is widely used in the preparation of aluminum alloy parts [37; 38]. Therefore, SLM technology is used to prepare tensile samples and lattice structures of aluminum alloy materials. In our experiments, an FS271M (Farsoon Technologies Co., Ltd., Hunan, China) selective laser melting (SLM) device was used for sample preparation (Figure 3). The samples were made of AlSi10 Mg (Farsoon Technologies Co., Ltd., Hunan, China), and their mechanical properties are shown in Table 2.  
After SLM molding tests, it was found that when the unit size was greater than 10 mm, a volume fraction between 15% and 45% was more conducive to forming. Therefore, we selected uniform TPMS porous structures with a cell size of 10 mm, period of 2 \(\times\) 2 \(\times\) 2, and volume fraction of 30% as the quasi-static compression experiments group (Figure 4). At the same time, three samples of uniform TPMS porous structures were prepared respectively. \begin{table}
\begin{tabular}{c c} \hline
**Property** & **Magnitude** \\ \hline Density (g/cm\({}^{3}\)) & 2.71 \\ Young’s modulus (GPa) & 70 \\ Yield strength (MPa) & 284 \\ Poisson’s ratio & 0.33 \\ \hline \end{tabular}
\end{table} 
Table 2: Mechanical properties of AlSi10 Mg.  
Figure 3: SLM (selective laser melting) 3D-printing equipment. Table 3 shows the specific characterization of print quality. The weight of the samples was measured by precision electronic balance (Zhengfeng Electronic Technology Co., Ltd., Suzhou, China), and their dimensions were measured by vernier calipers (Meinaite Industrial Co., Ltd., Shanghai, China). The compression test of the sample prepared using SLM was carried out using the LDW-100 kN microcomputer-controlled electronic universal testing machine (Jinan Ricks Measurement and Control Technology Co., Ltd., Jinan, China) to evaluate its mechanical  
Figure 4: The schematic diagram of the preparation of the porous triply periodic minimal surface (TPMS) structure compression samples by selective laser melting (SLM) technology. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{1}{c}{**Type**} & \multicolumn{1}{c}{**Weight (g)**} & \multicolumn{1}{c}{**Dimension**} \\  & & **(X \(\times\) Y \(\times\) Z mm)** \\ \hline \multirow{3}{*}{Gyroid} & Sample 1 & 7.00 & 19.92 \(\times\) 20.02 \(\times\) 19.52 \\  & Sample 2 & 7.03 & 19.92 \(\times\) 20.00 \(\times\) 19.82 \\  & Sample 3 & 7.01 & 20.02 \(\times\) 19.88 \(\times\) 19.62 \\ \hline \multirow{3}{*}{Diamond} & Sample 1 & 7.83 & 20.18 \(\times\) 20.20 \(\times\) 20.10 \\  & Sample 2 & 7.63 & 20.12 \(\times\) 20.18 \(\times\) 20.16 \\  & Sample 3 & 7.47 & 20.20 \(\times\) 20.00 \(\times\) 20.12 \\ \hline \multirow{3}{*}{I-WP} & Sample 1 & 7.58 & 19.82 \(\times\) 20.14 \(\times\) 20.26 \\  & Sample 2 & 7.58 & 20.02 \(\times\) 20.12 \(\times\) 20.20 \\  & Sample 3 & 7.22 & 20.12 \(\times\) 19.94 \(\times\) 20.18 \\ \hline \multirow{3}{*}{Neovius} & Sample 1 & 8.74 & 20.20 \(\times\) 19.92 \(\times\) 20.10 \\  & Sample 2 & 8.66 & 20.12 \(\times\) 19.98 \(\times\) 20.08 \\  & Sample 3 & 8.66 & 20.10 \(\times\) 19.94 \(\times\) 20.12 \\ \hline \multirow{3}{*}{Primitive} & Sample 1 & 6.88 & 19.88 \(\times\) 19.92 \(\times\) 20.00 \\  & Sample 2 & 6.76 & 19.92 \(\times\) 19.42 \(\times\) 19.92 \\  & Sample 3 & 6.66 & 19.92 \(\times\) 19.62 \(\times\) 19.94 \\ \hline \multirow{3}{*}{Fischer-Koch S} & Sample 1 & 8.46 & 19.72 \(\  
properties (Figure 5).