Iyer Ganapathi, Jayadurga (2012-02). Experimental Investigations of Properties of Magnetoactive Polymers. Master's Thesis.
Dynamic responses of the MR Elastomers and MR gel have been studied care- fully by various research groups. However, to understand completely the dynamic response of the material, it is important to have a clear understanding of quasi-static response of the material. Thus, for the current work, we have studied quasi-static response of the MR gel. For current setup, 27 samples were prepared using Septon, plasticizer and magnetic particles and were tested for 3 rounds over 3 different magnetic fields under plane strain compression. The results from plane strain compression show linear increase in the load taken with the increase in concentration of magnetic particles in absence of any magnetic field. The response characteristics under uniform magnetic field showed a huge leap in the load taken for particular deflection. To study the quasistatic respose, the material is assumed to behave like an isotropic hyperelastic response. Field dependent Neo-Hookean and field dependent Valanis Landel models have been fit to the data, and it was found that simple 1-term field dependent Valanis Landel model with power law coefficient as four agrees well with the shear modulus obtained from experiments. The shear modulus of MAP from the Valanis Landel and Neo Hookean model was assumed to be linearly dependent on the concentration of magnetic particles and magnetic field, and this matched the experimental data well.