Design methodology for functional gradient star-shaped honeycomb with enhanced impact resistance and energy absorption

Abstract

To enhance the impact resistance and energy absorption capacity of the honeycomb, a "gradient" design approach has been developed, incorporating the angle gradient, thickness gradient, and dual gradient star-shaped honeycomb (SSH). Subsequently, the impact mechanical properties of these gradient SSHs at various impact velocities are examined using numerical analysis. The results indicate that enhancing the initial stress peak and plateau stress of SSH, thereby improving its impact resistance and energy absorption rate, can be achieved through two modifications. Firstly, by configuring a layer with a smaller cell angle gradient at the impact end while utilizing a layer with a larger cell angle gradient at the bottom. Alternatively, by employing a layer with a larger wall thickness gradient at both the impact and fixed ends and a layer with a smaller wall thickness gradient in the middle. Furthermore, it has been observed that the deformation of dual gradient SSHs under dynamic loads is primarily governed by a thickness gradient. The results offer valuable insights that can be utilized in optimizing honeycomb structure design and investigating the mechanical properties influenced by the non-uniform distribution of honeycomb.