Crashworthiness analysis and optimization design of TPMS-filled structure

TPMS (triply periodic minimal surface) sheet structure consists of a spatially continuous surface, which forms a periodic porous structure, and has outstanding mechanical performance and ultralight weight. However, there are few studies on the periodic structure as an internal reinforcement energy absorber. In this study, we mainly discuss the collision ability of TPMS -filled square tubes under axial compression. Based on the numerical simulation results, it can be found that the unit-cell length and thickness of TPMS filler have great sway with the SEA and PCF of the TPMS-filled structure. The crashworthiness performance of TPMS-filled structures is better than the sum of separate structures attributed to the interaction effect. In addition, incomplete cell of the TPMS filler has a negative influence on the mechanical property at the low relative density and the shape of the TPMS filler can also affect the mechanical properties. To obtain an optimal TPMS-filled tube, a metamodel-based multi-objective optimization (MOO) method was employed to attain the Pareto front, in which the SEA is maximized and the PCF is minimized. It can be found that IWP-filled tube has maximum PCF among the four structures and FRD-filled tube owns maximum SEA.