Numerical study of impact energy absorption of auxetic structure

Abstract

3D printing technologies have helped researchers fabricate cellular structures and have lightweight and desirable mechanical properties. One such structure is called “auxetic” structures. “Auxetics” is the term used for structures that exhibit a negative Poisson’s ratio (NPR) and offer a wide range of wide range of potential applications in automotive, aerospace and military industries due to their great load-bearing capabilities in association with excellent energy dissipating performance. PLA (Poly Lactic Acid) material is used to 3D print eight different unit cell design. For each unit cell design with three different core thickness of 1.00 mm, 1.50 mm and 2.00 subjected to projectile impact with 10J of kinetic energy were studied by means of explicit nonlinear finite element simulations using LS-DYNA. Studies were carried out. The energy absorbed by the sample, contact force and projectile kinetic energy time history are compared and the damage on each sample is also compared. It was found that the Chiral unit cell absorbs the max energy and have less damage compared to other unit cell design.

Keywords

• auxetic structure
• pla
• explicit finite element simulation
• ls-dyna
• impact resistance