Analyses Of Magnetic Field And Magnetic-induced Shear Module For Composite Magnetorheological Elastomer Under Applied Field

Magnetorheological elastomers are composed of magnetic particles dispersed in an elastic matrix. Generally, elastomers are cured under a strong uniaxial magnetic field to fix chain-like, columnar structures of magnetic particles in the matrix. The MR elastomer can be controlled rapidly and reversibly by an applied magnetic, field. Such field-dependant characteristics of MR elastomers have attracted more interests in industrial applications.During the curing process, due to the magneto-rheological effect, the magnetic particles in the polymer matrix form a chain, columnar or layered ordered structure; After the curing, the ordered micro-structures are still kept in the matrix. This is one of the important features of the magnetorheological elastomers. This thesis focuses on the changes of the overall distribution of MRE’s magnetic field and the character of its magnetic shear modulus in the external one-way uniform magnetic field. Firstly, we used the homogenization theory to analysis the overall distribution of magnetic field in the ferromagnetic particles and the superelastic matrix in an external uniform magnetic field. Then, taking into account the microscopic structures of the composite material, we formulated the magnetic energies of MRE in the external uniform magnetic field. The magnetic dipole theory and the homogenization method were employed to calculate the magnetic-induced shear modulus of MRE, and results predicted by the two methods were obtained and compared.