The influence of the external magnetic field on acoustic properties of magnetic elastomers

The paper contains experimental results for the velocity of longitudinal acoustic wave, density, longitudinal elasticity modulus and viscosity coefficient of nanocomposite Fe-gel material with different percent content of iron nanoparticles. The concise description of the preparation technology of the samples under study is also included. The determination of the velocity and attenuation of the acoustic wave was based on the measurement of the change in the phase-frequency and insertion loss - frequency characteristics due to placing the samples between radiating and receiving transducers. The effect of magnetic field on the velocity of longitudinal acoustic wave has been also experimentally studied for the used samples. The method of the investigation was based on the measurement of the change in phase of output signal due to variation of magnetic field. It has been stated that the longitudinal modulus of elasticity increases with growing frequency of excited bulk acoustic wave and the velocity of longitudinal acoustic wave shows an enhancement up to 1.75 percent with the increase of magnetic field intensity to 10 kOe.