An Approach to Optimize the Mechanical Properties of Cylindrical Negative Stiffness Structures

Abstract Negative stiffness (NS) structure, as a type of mechanical metamaterial, possess numerous excellent properties and has broad potential applications in areas such as impact energy absorption, vibration damping, and noise reduction. However, their energy absorption efficiency is not high. Typically, incorporating fillers into honeycomb structures proves to be an effective strategy for augmenting the mechanical properties of honeycomb materials. In this study, we propose a model for a filled cylindrical NS structure (CNS), where the fillers are treated as springs to facilitate finite element simulation. Subsequently, we further investigate the fundamental mechanical properties and energy dissipation capacity of unfilled CNS structures as well as filled CNS structures employing distinct types of fillers, including linear elastic and viscoelastic fillers. The results indicate that linear elastic fillers do not have a positive impact on improving the energy dissipation capacity of CNS structures but can be used to adjust the response curve. When viscoelastic fillers are filled inside the CNS structure, they can effectively enhance the strength and energy dissipation capacity of the CNS structure. Moreover, the approach presented in this investigation holds significant reference value for the design of various mechanical metamaterials based on NS structures.