Optimum design for energy absorption of Functionally Graded Honeycomb FGH filled tube under oblique impact loading

In automobile industry crash boxes as an element which is generally inserted between chassis and bumper dissipate the impact energy of collision through plastic collapse in a controlled manner. In more collision events, crash boxes are not only subjected to axial impact loading, but also these elements experience both axial and oblique impact loading. In this article, nonlinear parametric finite element simulations of FGH filled tubes were developed and the effect of density grading on crashworthiness parameters such as specific energy absorption SEA and initial peak load are investigated and optimized through two multiobjectives methods Constrained single-objective optimization and weighted average method. It is believed that the crashworthiness of functionally graded honeycomb (FGH) structure subjected to oblique impact loading can improved in comparison with uniform density foam by a proper selection of metallic honeycomb density exponent gradient m in this study.