Bending Behavior of Sandwich Panels with Auxetic Cores

Sandwich panels are used in various engineering applications due to their excellent mechanical properties such as high stiffness, strength and energy absorption. Cores always play an important role in mechanical performance of sandwich panels. Auxetic structures have attracted a lot of attention in recent years. These structures have negative Poisson's ratio, which improves their performance in energy absorption, resistance to deformation, and resistance to crack growth. In this paper, two auxetic cores based on re-entrant and arrow-head cores are designed and investigated. Using finite element analysis (FEA), Poisson's ratio, flexural stiffness and flexural strength of sandwich panels are determined and compared with each other. Results show that the designed sandwich panels have better flexural performance than the original re-entrant and arrow-head panels. Results also approve that the method of hybridizing several auxetic cores to achieve optimized core is effective.

Keywords:

sandwich panels , auxetic structures , finite element analysis , three-point bending , four-point bending