The influence of hydrostatic pressure and transverse magnetic field on the electric conductivity of the magnetorheological elastomers

Two sets, each of five samples, of magnetorheological elastomers (MREs) based on silicone rubber and carbonyl iron were prepared. One set of samples was obtained by polymerization of the silicone rubber with additives in the absence of the magnetic field, while the other by polymerization of the silicone rubber with additives in the presence of the magnetic field (840 kA/m). The samples from each set differ by volume concentration of the magnetic phase. By means of an experimental setup described in the paper, the electrical resistance R of the samples was measured as a function of the force F applied on the surface of the samples, for fixed values of the transverse magnetic field strength H. From the as-measured dependence R = R(F)H, the dependence σ = σ(p)H of the electric conductivity σ on the applied pressure p was determined. The experimental results are discussed in view of possible applications like magneto-mechanical sensors working in hostile media.