Thermoresistance and giant magnetoresistance of magnetorheological elastomers

Abstract

A new magnetorheological elastomer composite (MRE) 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 pressure for seven different values of the temperature. The mechanism of electrical conduction was modeled and assessed experimentally. An other type of composite, prepared with a softer elastomer, showed a giant magnetoresistance with a decrease by 3 orders of magnitudes for a field of only 100kA/m (1250Oe); It was shown that the magnetic pressure acted like mechanical pressure for field lower than 100 kA/m but beyond the magnetoresistance was saturating contrary to piezoresistance.

Magnetic field dependent electro-conductivity of the graphite doped magnetorheological plastomers

“…The addition of the conductive doping is the most common method for improving the conductivity of the MR materials [23][24][25]. Li et al developed the high performance MREs with excellent mechanical and electrical properties by using graphite 5 as the additive [26,27].…”

Magneto-piezoresistance in elastomagnetic composites

“…In spite of this logical prediction, the coupling between the magnetization status and the resistance in magnetic elastomers was rarely investigated. 14,15 This paper reports a magneto-piezoresistance (MPR) effect in an elastomagnetic composite that gives a resistance decrement of about 60% under a magnetic induction field gradient of 3 T/m. The investigated composites were bar shaped samples made of Ni microparticles (Ni MPs) dispersed into a silicone matrix, in a volume fraction (vol%) of about 40%.…”

Magnetorheological elastomer-based quadrupolar element of electric circuits

“…The iron microparticles are connected to the polymer chains of the elastic matrix [3,9,13,23,25]. Then, due to the action of F, the elastic matrix reacts with the elastic force F el .…”

“…It has been recently shown that MRSs modify their conductivity by compression [22,23], heating [24], under the influence of an external magnetic field [25].…”