Dynamic Response of 3D-Printed Bi-Material Structure Using Drop Weight Impact Test

Additive manufacturing has led to increasing number of applications that require complex geometries and multiple materials. This paper presented a bi-material structure (BMS) composed of a cushion matrix held by a 3D printed frame structure for an improved impact resistance. The study mainly focused on understanding the effects of structural topology and matrix material. Two matrix materials, silicone elastomer and polyurethane (PU) foam, were selected to impregnate into two different PLA frame structures. Drop weight impact test was carried out to measure the impact force and energy absorption. The results showed that the overall impact resistance was dominated by the frame, while the matrix reinforcement required proper structural interlocking mechanism and material matching. In the particular specimens of this study, PU foam led to more energy absorption and force bearing capacity of the structure than the silicone elastomer.