FIELD DEPENDENCE OF VISCOELASTIC PROPERTIES OF MR ELASTOMERS

A magnetoactive elastomer made of micronic carbonyl iron particles, structured in elongated clusters and embedded in a silicon elastomer matrix is studied under traction both in static and dynamic modes. The application of a magnetic field of 120 kA/m induces a change in elastic moduli of about 0.6 MPa at strains of 4 to 5%. Still higher changes (4 MPa) are observed in dynamic storage modulus at low strains (10-4 to 10-3). The shape of the stress-strain curves are explained by taking into account the existence of a fiber like structure.