## 4 Conclusions  
In this paper, TPMS modeling and triangulation are realized based on MATLAB, and quasi-static compression tests are carried out on periodic porous TPMS structures printed by SLM. Subsequently, combined with the joint simulation of Hypermesh and Abaqus to realize the axial compression simulation of porous TPMS structure, the deformation mechanism, mechanical response, and energy absorption characteristics of different porous TPMS structures under axial quasi-static compressive loads are systematically analyzed. Finally, the Gyroid and Primitive structures with excellent mechanical properties are selected as the inner core to design the automotive energy-absorbing box. The boxes are printed via SLM. Combined with low-speed impact experiment and simulation, the deformation mechanism, impact resistance, and energy absorbing properties of crash boxes filled with porous TPMS structures were compared with those of the traditional thin-walled crash box. The key findings from this research are summarized below. 1. Structural failure of the porous TPMS structure along the surface shear bands under axial quasi-static compressive loading conditions. Deformation is dominated by layered bending collapse, which stabilizes structural deformation while reducing peak loads. 2. The load-displacement curves of the porous TPMS structures (Gyroid and Primitive) subjected to external loads fluctuate smoothly. The more prominent the shear defor  
Figure 16: The comparison between specific energy absorption values of porous triply periodic minimal surface (TPMS) structures, bio-inspired structures, and other composite structures. mation of the porous TPMS structure, the less the fluctuation degree of the platform section affected by the single load. 3. The energy-absorbing box filled with porous TPMS structures is attributed to a particular deformation behavior. The failure form of layer-by-layer collapse provides it with high-quality energy absorption capacity, and its peak load and load fluctuation are significantly reduced compared with traditional thin-walled energy-absorbing boxes. On the premise of ensuring lightweight and energy absorption requirements, a new solution is provided for solving the problems of excessive peak load and unstable load fluctuation of traditional thin-walled energy-absorbing boxes. 4. Comprehensive analysis shows that the porous TPMS structure has the advantages of eliminating stress concentration and improving mechanical strength. Automobile energy absorbing boxes filled with porous TPMS structures have excellent impact resistance and energy absorption characteristics compared with traditional thin-walled energy-absorbing boxes. The porous TPMS structure is an ideal candidate for lightweight multifunctional structures. 5. The research is based on SLM to realize the lightweight design of automotive energy-absorbing boxes and to provide the basis for the selection of other parts. Additional research should be carried out on the influence of the parameters of additive manufacturing and the selection of raw materials on the mechanical behavior of porous TPMS structures. Through the matching of different additive manufacturing technologies and excellent raw materials, combined with the topological optimization of porous TPMS structure, the integrated design of goal-material-structure-function can be achieved. Conceptualization, X.Z. ([PERSON]) and Z.L. ; formal analysis, Z.L. and X.Z. ([PERSON]); methodology, X.Z. ([PERSON]); software, X.Z. ([PERSON]); supervision, Z.L. ; validation, X.Z. ([PERSON]); visualization, X.Z. ([PERSON]); writing--original draft, Z.L. and Y.Z. ; writing--review and editing, Z.L. and Y.Z. All authors have read and agreed to the published version of the manuscript. This research was funded by the National Natural Science Foundation of China (grant number: 51705534) and the Natural Science Foundation of Shandong Province (grant number: ZR2022 MF291). The data presented in this study are available upon request from the corresponding author.