Magnetorheological elastomers: properties and applications

Magnetorhelogical (MR) elastomers are viscoelastic solids whose mechanical properties are controllable by applied magnetic fields. We have developed a family of MR elastomers, comprising micrometer-sized carbonyl iron particles embedded in natural rubber, that can be processed using conventional rubber-mixing techniques. By crosslinking the elastomer in the presence of an applied magnetic field, field-induced interparticle interactions promote the formation of particle chains and columns aligned along the field direction. The resulting composites possess field- dependent of the mechanical properties of MR elastometers enables the construction of controllable elastomeric components, such as suspension bushings, that may prove advantageous in some automotive applications.