Design Of Negative Stiffness Strueture And Research It's Endoenergetic Characteristic

With the rapid development of aerospace and other engineering technology,the demand for lightweight energy-absorbing materials has become even more urgent.This kind of lightweight material with high compressive strength and energy absorbing ability usually has special microstructure,and the geometrical properties and relative density of these microstructures directly determine its macroscopic properties.On the other hand,taking into account the application of such structures usually involves multiple loading,the recoverability after deformation is also an important feature.Based on the above background,several negative stiffness structures are designed and studied their energy absorption.In this paper,we study the negative stiffness structure of th e composite corrugated plate.This is a kind of structure composed of corrugated and T-shaped tandem.Because of the large structural rigidity of T-shaped platform,the macroscopic characteristics of this structure are mainly composed of Corrugated plate.The influence of the angle and thickness of the corrugations on the negative stiffness and energy absorption characteristics of the structure is studied by finite element simulation.Secondly,this paper designs a reusable three-dimensional negative stiffness structure,and explores its preparation process.Designed to find suitable materials,making the structure both with high compressive strength and energy absorption capacity,but also can be reused.The study of the three-dimensional negative stiffness structure is divided into two parts,namely,the design and preparation of the structure,and the optimization based on the finite element simulation.In view of the design and preparation of the three-dimensional negative stiffness structure,this paper studies the theoretical derivation of the mechanism of the hyperbolic deformation of the curved beam,and has a better understanding of the force and deformation of the structure.Then,three-dimensional high density and low density structures are proposed according to the shape and geometry of the single cell.These two types of negative stiffness honeycomb structures can be obtained by combining the negative stiffness honeycomb cells through a circular array and a linear array,or combined by two-dimensional negative stiffness honeycomb panels.Cutting,locking assembly and brazing process can be used for preparation.you can use nickeltitanium alloy plate or 304 stainless steel plate to prepare.We used 304 stainless steel plate to prepare the model for the experiment.3D printing can also be used to prepare,but to use the appropriate material.Whether embedded lock assembly or 3D printing are based on the characteristics of the material,we should find the appropriate material for preparation.Moreover,the structure is optimized by adjusting the geometric dimension of the structure,and the idea of adjustable structure stiffness is proposed.In the literature,the idea of optimizing the two-dimensional negative stiffness honeycomb structure is proposed,and the optimization of the two-dimensional negative stiffness honeycomb is according to change the geometric dimensions.For the design of the threedimensional structure,we also optimize the geometric size,to study the impact on structural characteristics of the negative stiffness and energy absorption by changing the parameters.The purpose of optimization is to reduce the relative density of the structure and improve its energy absorption capacity.In order to achieve this goal,this paper uses the finite element software ABAQUS to simulate the structural deformation,calculate the energy absorption characteristics of different geometric dimensions structures,and obtain the optimal structure by contrast.In view of the above three parts,this paper has carried on the detailed analysis and the research,and has explored the influence of the geometric parameter and the material parameter to the negative stiffness of the structure.In addition,this paper designs a reusable corrugated plate combined negative stiffness structure and threedimensional negative stiffness structure,which is optimized.In addition,the preparation of three-dimensional negative stiffness structure is also discussed.This study will help to promote the application of negative stiffness structure in engineering,but also to provide new ideas for "structure to determine the performance".