Magnetic Field-Induced Deformation of Isotropic Magnetorheological Elastomers

Abstract

In our research, the magnetic field-induced deformation of isotropic magnetorheological elastomer (MRE) discs loaded with two types of magnetite and an iron powder were examined. A measurement system using a microscope camera was assembled, and the magnitude of the deformation was determined from the optical contour obtained with digital image processing. We found that the MRE discs with a height-to-width aspect ratio of 1:2 underwent expansion in the direction of the external field in all cases. The magnitude of the dilatation increased with the magnetic field strength in cases of all filler materials, but the exact trend depended on the type and concentration of the filler. An inhibition of the polymerization of the matrix was observed in the case of one of the magnetite fillers, which resulted in a decreased zero-field elastic modulus at higher particle loadings. A correlation was found between the reduced elastic modulus and the increased magnitude of the deformation.

Keywords

• magnetorheological elastomers
• deformation
• elastic modulus
• external magnetic field