Abstract:

Aluminum foam filled thin-walled structure has light weight, large bearing capacity and high efficient energy absorption characteristics, and it had widely applied in different kinds of engineering structures. A novel functionally graded foam (FGF) filled structure is presented, and the mechanical response and energy absorption characteristics of empty tube (ET), uniform tube (UFT) and functionally graded foam tube (FGFT) under bending condition are studied by using experiment and numerical analysis method. It is found that the FGFT has more excellent anti-bending behavior than ET. Moreover, FGF not only changes deformation mode of thin-walled structure from single fold pattern to multi-folds pattern, and reduces the cross section flattening and the loss of rigidity, but also effectively improves carrying capacity and energy absorption characteristic of the thin-walled structure. Besides, to further explore the optimal crashworthiness of foam-filled structure, the numerical optimization is performed about UF and FGF thin-walled structures based on Kriging approximation technique and the particle swarm optimization algorithm (PSO). Lastly, optimal design parameters of foam-filled thin-walled structures are obtained, meantime, the bend resistance of foam filled structures is improved efficiently. Therefore, the optimal design provides a reference for bend resistance design for the foam filled thin-walled structure.

Key words: crashworthiness, multi-objective optimization, three points bending, foam filled structure