Drop-Weight Impact Behavior of Three-Dimensional Printed Polymer Lattice Structures with Spatially Distributed Vertical Struts

Three-dimensional (3D) printed polymer lattice structures of different configurations are investigated in this research to study their behavior under low-velocity impact load. The Body Centered Cubic (BCC) is modified and redesigned to generate three additional sets of the lattice structures to compare their impact energy absorption capability. The modified designs are (a) BCC with vertical struts connecting all nodes (BCCV) (b) BCC with vertical bars connecting alternate nodes (BCCA), and (c) BCC with gradient distribution of struts (BCCG). All the four sets are created using Acrylonitrile Butadiene Styrene (ABS) polymer material on a Stratasys uPrint 3D printer. An in-house built ASTM Standard D7136 drop tester was used to capture the impact response. Data obtained from the attached accelerometer is post processed to find velocity, displacement, transferred energy, and force histories. The absorbed energy is found from the change in kinetic energy of the impactor before and after impact. It is observed that the selective placement of vertical support struts in the thickness direction influences the impact response of lattice structures.