Abstract: To enhance the flatwise compression property of BCC structures, an optimization design is performed using periodic boundary conditions coupled with the ESO method, and it is found that the equivalent compressive modulus of the topologically optimized BCC unit cells significantly surpasses that of traditional BCC cells. The flatwise compression simulation model of the 4×4 core structure composed of optimized unit cell is constructed in the ABAQUS software, followed by a comparative compressive experiment to demonstrate the feasibility of the simulation model. Comparison analysis between traditional structures and topologically optimized structures under compressive loads shows that the peak force in the optimized model is increased by 79.2%, and the effective energy absorption is enhanced by 48.5%. The specific energy absorption per unit volume and per unit mass is augmented by 47.8%. The optimization based on the BCC cell, not only significantly increases the equivalent compressive modulus of the BCC cells but also results in better energy absorption property under compressive loads.

Key words: composites, periodic boundary condition, topology optimization, flatwise compression, energy absorption