Graded Foam Research Articles

Crush behavior optimization of multi-tubes filled by functionally graded foam

Crush behavior of different arrangements of multi-tubes filled by functionally graded foams (FGF) are evaluated in this study. Our study shows that the energy absorption of FGF filled multi-tubes is higher than their equivalent multi-tubes filled by uniform foams. Also, the results show that the type of function employed for grading foam has significant effect on their crush response. In this study, multi-objective optimization was carried out using geometrical average and multi-design objective (MDO) methods. The results give new design ideas under axial loading to improve energy absorption performance of FGF foam-filled tubes.

Penetrating Resistance of the Laminated Composite with Stepwise Graded Foam

The present study focuses on the penetrating resistance of the laminated composite with stepwise graded foam target struck normally by conical-nosed projectiles. The dynamic cavity expansion theory is applied to formulate analytical model. Experimental results verify that this model on account of rigid-perfectly plastic-locking model is suitable for analyzing penetration depth of the projectile into a cellular target. The difference types of foam configurations, with identical areal density, were arranged according to the density of the respective foam. The penetrating process can be divided into 7 stages. Penetrating depth; the effect of mass density and the change of graded/layered core structures of the difference configurations are analyzed. It is found that composite target have a higher penetrating resistance than the monolithic foam material target of equal mass. The analytical results show great potential to reasonable structures for absorbing the dynamics energy and improving the overall penetrating resistance.