Study Of Cushioning Properties Of Weaire-Phelan Structures

The structure of cushioning material has an important influence on its cushioning performance.With the increasing requirement of product packaging,the requirement of cushioning is also become higher,which urge experts and scholars to explore the cushioning structure with better cushioning performance.In recent years,the improvement of common honeycomb structure and corrugated structure have been carried out.At the same time,more and more researchers have also done a lot of research on the cushioning performance of porous structure used as cushioning packaging structure in other fields.In this dissertation,the dynamic analysis of Weaire-Phelan cushioning structure was carried out based on finite element method.At the same time,the Kelvin and honeycomb cushioning structures were compared with Weaire-Phelan cushioning structure.This dissertation provides a reference for the design of Weaire-Phelan cushioning structure.In this dissertation,the Weaire-Phelan cushioning structure was chosen as the research object,and the following work were carried out:Firstly,the CAD of cushioning structure was established,and then its 3D printed products were made.Secondly,the Weaire-Phelan cushioning structure was analyzed by using the finite element method.The uniaxial compression test of the rubber material used in the finite element analysis was carried out to obtain the related material parameters.Two kinds of cell density Weaire-Phelan cushioning structures which had the basically close model volume and the same volume of materials were designed and their finite element models were also established..The drop impact of the two cushioning structures were analyzed and compared under three kinds of mass and three heights.The results indicated that the drop-impact process of Weaire-Phelan cushioning structure is nearly the same as that of common porous structure deformation process.It is found that the mechanical properties of the cushioning structure are enhanced with the increase of the initial strain rate;the drop mass has little effect on the initial stress peak and the platform stress of the cushioning structure;and the cushioning structure with higher cell density has higher platform stress,while the energy absorption performance decreases slightly.Finally,the cushioning performances of Weaire-Phelan,Kelvin and honeycomb cushioning structures were compared.During the whole compression process,Weaire-Phelan and Kelvin cushioning structures are two-way gradual collapse process from bottom to top and from top to bottom,while the collapse mode of honeycomb cushioning structure is folded gradually.Compared with the Weaire-Phelan cushioning structure,the honeycomb and Kelvin cushioningstructures have obvious inward depression in the middle of the cell wall.The stress-strain curves of three kinds of cushioning structures are obtained and suggested that,the mechanical behavior of drop impact is greatly affected by the initial strain rate.In the on-line elastic stage,the honeycomb cushioning structure has the maximum stress peak.After entering the platform stage,the Weaire-Phelan cushioning structure has the maximum platform stress.The energy absorption curves of Weaire-Phelan,Kelvin and honeycomb cushioning structure show that the energy absorption characteristics of drop impact are greatly affected by the initial strain rate;the optimal energy absorption shoulder points of honeycomb cushioning structure,Kelvin cushioning structure and Weaire-Phelan cushioning structure move gradually to the upper and right;the standardized energy and standardized stress value corresponding to the same energy absorption in the platform stage increase in turn.These results indicate that the Weaire-Phelan cushioning structure has excellent energy absorption characteristics and impact bearing capacity.