Thermoresistance and giant magnetoresistance of magnetorheological elastomers

A new magnetorheological elastomer (MRE) composite was developed with a resistance which is strongly sensitive both to temperature and pressure. The electrical resistance of this MRE was investigated versus pressure and temperature. The resistance of the composite was recorded versus the pressure for seven different values of the temperature. The mechanism of electrical conduction was modelled and assessed experimentally. Another type of composite, prepared with a softer elastomer, showed a giant magnetoresistance (MR) with a decrease by three orders of magnitude for a field of only 100 kA m−1 (1250 Oe). It was shown that the magnetic pressure acted like mechanical pressure for fields lower than 100 kA m−1 but beyond the MR was saturating contrary to piezoresistance.