The Structure Analysis And Optimization Of Magnetorheological Elastomers Thin Plate

With the rapid development of machinery industry,aerospace,architecture and medical fields,the research on intelligent materials and intelligent structures is more and more important.As a new intelligent material,the magnetorheological elastomer(MRE)can significantly improve its elastic modulus under the action of the magnetic field,and it has the characteristics of no seal,stable performance and rapid response,so it has great application prospect in the control of structural stiffness.At present,the research on magnetorheological elastomers is still in the laboratory research stage.How magnetorheological elastomers affect the mechanical properties of materials and consequently affect structural performances is still lacking in sufficient research.Therefore,the calculation of magnetic shear modulus,structural analysis and optimization of magnetorheological elastomers is presented in this paper.Firstly,the micro structure of magnetorheological elastomers is simulated,and some physical quantities related to the properties of the materials are obtained.Then,the data are processed and the relative permeability of the equivalent element of the magnetorheological elastomer is calculated,which is close to the experimental results in the literature.The magnetic shear modulus of the magnetorheological elastomer under different particle volume fraction and different magnetic field strength is calculated,which is consistent with the experimental results.At the same time,the magnetic shear modulus under different particle gap and different particle shapes is also calculated.Secondly,the thin plate made of MRE in magnetic field is studied and the structure analysis is carried out under different magnetic field intensities.The influence of magnetic field on the deflection of MRE thin plate under static load is calculated and the numerical results show magnetic field can effectively reduce the deflection.The influence of magnetic field on the natural vibration frequency of the MRE thin plate is also analyzed and the numerical results show the natural frequency of vibration increases with the increase of the magnetic field,but decreases with the increase of the particle concentration.The critical buckling load of the MRE thin plate under mechanical load and magnetic field is calculated and results show that the critical buckling load increases significantly with increases of the magnetic field intensity and the particle concentration.Also,the critical buckling load of the MRE thin plate under the magnetic field,the electric current and mechanical load is computed.It is concluded that the magnitude and direction of the electric current have a crurcial effect on the critical buckling load.Finally,the method of design optimization of MRE thin plate is proposed,In this investigation,the particle volume of each element in the magneto-elastic thin plate is taken as the design variable,and the mass of the thin plate(the sum of the mass of the particles and of the matrix)is taken as the constraint condition,the rectangular MRE thinning plate is optimized with the specified displacement as the the objective function.After the optimization,a reasonable distribution of the particle volume can be obtained and the specified displacement is obviously reduced,which shows the effectiveness of the optimization method.