Abstract:  In order to meet the higher requirements of energy absorbing structure in the lightweight design of automobile, the mechanical design and impact energy absorption of plate cubic lattice are studied. Three kinds of basic cell structures of the plate-like cube, simple cube (SC), body centered cube (BCC) and face centered cube (FCC) are designed, and two composite cell structures SC-BCC, SC-FCC are obtained by combining the basic cells. The deformation mechanism and mechanical response of BCC, FCC, SC-BCC and SC-FCC lattice structures are analyzed systematically, and the energy absorption performance of four structures under 10 and 50 m/s impact velocity are evaluated and compared. The results show that the peak load of the energy absorbing box filled with plate cubic-lattice core is less than 100 kN under 4.4 m/s impact, and the average load is almost equal to the peak load, and the specific energy absorption (SEA) of the composite lattice core filled energy absorption box is higher than 32 J/g. Comparative study found that the plate-like cubic lattice has excellent impact resistance and energy absorption characteristics, and has a broad application prospect in the field of lightweight automobile passive protection.

Key words: automobiles, lightweight design, energy absorbing boxes, impact energy absorption, plate cubic lattices, quasi-static compression, impact dynamics, simulations