Study On Vibration And Damping Of Negative Poisson’s Ratio Structure Of Composite Material

As a new generation of energy-absorbing structure,negative Poisson’s ratio structure has received extensive attention in academic and engineering field.At present,an abundant amount of study has concentrate on the manufacturing techniques,statics performance and impact energy absorption of negative Poisson’s ratio structure.However,the study on the vibration and damping performance of negative Poisson’s ratio structure of composite has just started.In this dissertation,based on the structural damping integration technique,a new type structure of the double-arrow composite structure,concave-cellular composite and the corrugated sandwich structure with damping capacities are designed.Based on numerical simulations and experiments,the vibration damping characteristics are investigated.The main contents are as follows:Firstly,the two-dimensional double-arrow composite structure and concavecellular composite structure are proposed and designed.The vibration damping characteristics are studied by finite element modal strain energy method.The influence of different structural geometry parameters on the vibration damping are discussed.The results show that the structural geometry parameter can significantly influence natural frequency and damping loss factor of the two-dimensional doublearrow composite structure and concave-cellular composite structure.Secondly,on the basis of two-dimensional negative Poisson’s ratio structure,the three-dimensional double-arrow structure and concave-cellular structure are proposed and designed.The influences of different fiber orientations and structural geometry parameters on the vibration damping are discussed.The researches show that compared to the concave-cellular structure,the vibration damping of threedimensional double-arrow structure is more sensitive to the change of the angle of structure.Finally,the negative Poisson’s ratio corrugated sandwich structure with damping capacities are fabricated by a hot press moulding integrated method.And the vibration damping characteristics which are influence by the location and material species of the damping capacities are studied by numerical simulations and experiments.The results show that compared with the structure stiffness of the negative Poisson’s ratio corrugated sandwich structure,the damping loss factor of the structure with damping capacities has a significant Improvemet.