Dynamic Response of 3D Printed Bio-Inspired Lightweight Structures
摘要
The study investigates the mechanical response and damage tolerance of 3D-printed cornstalk-inspired structures (porous, lightweight) manufactured using Acrylonitrile Butadiene Styrene (ABS) material. Specimens were subjected to localised impact (dynamic indentation tests) with a conical-shaped indenter at 90 J impact energy. The base polymeric material (ABS) was characterized across varying strain rates using Shimadzu® Universal Testing Machine and Split Hopkinson Pressure Bar. A homogeneous (uniform density) specimen was prepared to compare the damage resistance of cornstalk-like geometry using a drop-weight impact test. The results demonstrated that the homogeneous specimen weighed ~39% more than the bio-inspired specimen and exhibited ~28% lower energy-absorbing capability. Damage characteristics of the damaged specimens were interrogated through X-ray CT scans and provided detailed failure modes associated with conical indenter. Further, finite element simulations (using LS-DYNA) were undertaken to compare the experimental results and validate the identified mechanical properties of ABS polymer. These lightweight structures have the potential to be used in the sports industry, i.e., protection helmets.