Novel multifunctional negative stiffness mechanical metamaterial structure: Tailored functions of multi-stable and compressive mono-stable

In this study, a new negative stiffness metamaterial (NSM) is designed using laminates with independent negative stiffness (NS) properties as the functional component and a discrete assembly method. In this paper, the metamaterial is designed by mathematical model, which have been verified and analyzed systematically by experiment and finite element (FE) method. The influence of each laminate parameter on the design of metamaterials under uniform distribution and gradient distribution was investigated, and based on this, the load-bearing capacity enhancement strategy of metamaterials was further explored. The metamaterial has the advantages of discrete assembly and designability, which solves the defects of the previous performance constrained by the structure and enhances the usability.

Section: Design Model Of Nsmmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

A novel negative stiffness metamaterials: discrete assembly and enhanced design capabilities

Sun

Zhang

Guo

et al. 2023

“…These properties are determined by the special artificial structure rather than its material composition. In recent years, various metamaterials have developed rapidly, such as negative Poisson's ratio structures [5][6][7][8][9][10][11][12][13], lightweight high-strength structures [14][15][16][17] and negative stiffness (NS) structures [18][19][20][21][22][23][24][25][26][27]. * Author to whom any correspondence should be addressed.…”

Section: Introductionmentioning

confidence: 99%

A self-recoverable negative stiffness metamaterial with enhanced bearing and energy dissipation capacity

Lv,

Li,

Ren

2024

Because of their desirable properties, mechanical metamaterials have drawn increasing attention. Negative stiffness (NS) metamaterials can be used as reusable energy dissipation devices, but they usually have low bearing capacity. In this study, a self-recoverable NS structure with enhanced bearing and energy dissipation capacity was proposed. It breaks free from the size limitations of curved beams or thin rods, and can have high bearing and energy dissipation capacity through the mutual extrusion and friction between the snap plug and the layered snap groove. The mechanical properties of the proposed NS structure were studied by finite element analysis (FEA) and experiments. The reusability of the structure was verified by cyclic loading experiments. The results show that compared with the traditional curved beam NS structure and the previously self-recoverable NS structure, the bearing and energy dissipation capacity of the proposed structure have been greatly improved.

“…During buckling in a member of the NSS, with an increase in the applied compressive loading, a force-drop occurs, a snap-through mechanism is activated in the structure, and it reveals an NS behavior [14]. Such structures have been used as actuators [15,16], bumpers [17], energy absorbers [18][19][20][21][22], and vibration absorbers [23,24]. While other energy absorber structures such as auxetics are disposable, NSSs have the advantage of multiple-use applications [25][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

3D printed negative stiffness meta-structures with superior energy absorption and super-elastic shape-recovery features

Hosseinabadi

Etemadi

Serjouei

et al. 2023

The aim of this paper is to create novel 3D cubic negative stiffness structures (NSSs) with superior mechanical performances such as high energy absorption, shape recovery, super-elasticity, and reversibility. The conceptual design is based on an understanding of geometrical influences, non-linear buckling-type instability, snap-through mechanism, elasto-plastic deformation growth and plastic hinges. A finite element (FE) based computational model with an elasto-plastic material behavior is developed to design and analyze NSSs, saving time, material, and energy consumption. Material samples and meta-structures are 3D printed by selective laser sintering printing method. Material properties are determined via mechanical testing revealing that the printing process does not introduce much anisotropy into the fabricated parts. Experimental tests are then conducted to study the behavior of novel designs under loading-unloading cycles verifying the accuracy of the computational model. A good correlation is observed between experimental and numerical data revealing the high accuracy of the FE modeling. The structural model is then implemented to digitally design and test NSSs. Effects of the geometrical parameters of the negative stiffness members under three cyclic loading are investigated, and their implications on the non-linear mechanical behavior of NSSs under cyclic loading are put into evidence, and pertinent conclusions are outlined. In addition, the dissipated energy and loss factor values of the designed structures are studied and the proposed UC is presented for the energy absorbing systems. The results show that the structural and geometry of energy absorbers are key parameters to improve the energy absorption capability of the designed structures. This paper is likely to fill a gap in the state-of-the-art NS meta-structures and provide guidelines that would be instrumental in the design of NSS with superior energy absorption, super-elasticity and reversibility features.