Dynamic impact behaviors of functionally graded lattice structures

With the characteristics of light weight, high strength, good shock absorption ability, the lattice structures have drawn a lot of attention [1-9]. On the other hand, functionally graded materials are typically inhomogeneous composite materials, which can apply to extremely working conditions [10-15]. In this paper, the design concept of functionally graded materials is introduced to the lattice structures, in order to accomplish the multi-function optimization design of the lattice materials. The impact performances of the functional graded lattice structure with regular and staggered quadratic cells are studied, respectively. Under the different impact velocities, the influences of the cell arrangements of the deformation modes and energy absorption are analyzed. The results shows that for the same relative density and impact velocity, the lattice structures with regular arrangement is superior to the ones with staggered arrangement on the energy absorption ability. The reasons are revealed by the micro structures of the cells and the macroscopic deformation mechanism. Moreover, the influences of the density gradients on the deformation modes and the energy absorbing abilities are investigated. This paper is helpful for the design and analysis of the mechanical characteristics of the lattice materials and structures.