Magneto-piezoresistive characteristics of graphene/room temperature vulcanized silicon rubber-siliconrubber magnetorheological elastomer

The effect of graphene with different content on the magneto-piezoresistive characteristics of graphene/room temperature vulcanized silicon rubber (GR/RTV) magnetorheological elastomer (MRE) was studied, and the relationship between the content of graphene and conductivity of GR/RTV-MRE was described based on the general effective medium theory. A magneto-piezoresistive model was established to describe the relationship among resistance, pressure, and magnetic field based on the magnetic dipole and tunneling theory. The samples of GR/RTV-MRE with different content of graphene were prepared. The experimental platform with magneto-piezoresistive characteristics controlled by magnetic field was built. The effect of graphene with different content on piezoresistive coefficient of GR/RTV-MRE was obtained under different magnetic flux density. The experimental results showed that the piezoresistive coefficients of samples with different content of graphene decrease with the increase of magnetic flux density in the range of 0 similar to 80mT. For the same magnetic field, when the volume fraction of graphene is less than 12%, the piezoresistive coefficient is positively correlated with it, when the volume fraction of graphene is more than 12%; the increase of content has little effect on the piezoresistive characteristics. The experimental results are compared with theoretical calculations for correction and error analysis. The results showed that the modified model can well describe the variation of the resistance of GR/RTV-MRE under magnetic field and pressure.