Dynamic rheological properties of polyurethane-based magnetorheological gels studied using oscillation shear tests

Abstract

This paper studies the dynamic rheological behaviors of magnetorheological (MR) gels containing different CIP weight fractions suspended in polyurethane (PU).

Solvent Dependence of the Rheological Properties in Hydrogel Magnetorheological Plastomer

“…The increased loss factor at the higher strain caused by strain hardening is due to the rupture of polymer chains that increased the dissipation energy. This phenomenon was observed in plastic materials as reported in previous research [36]. Sample 1 shows larger strain hardening compared to Samples 2 and 3 because the liquid-like nature of the matrix caused more dislocation of the polymer chains, thus increased the loss factor.…”

Magneto-induced rheological properties of magnetorheological gel under quasi-static shear with large deformation

“…34 Therefore, the gaps between the steady-state value of storage modulus decrease progressively with the increasing of magnetic elds. 35 On the other hand, taking MRG-40 for example, storage modulus appears a rising trend with the enlargement of frequency at rst and then gets a plateau gradually. Fig.…”

“…It found that the instantaneous and stable modulus of MRG with ordered chain-like microstructures are larger than those of MRG with unordered microstructures in the absence of a magnetic eld. 21 Zhang et al 22 carried out the static and dynamic shear tests to study the rheological properties of polyurethane-based MRG. The static experiments indicated that, compared with other factors, the magnetic eld has a stronger inuence on the rheological properties.…”

Normal force of lithium-based magnetorheological grease under quasi-static shear with large deformation

“…viscosity, yield stress, storage modulus and loss modulus. [11][12][13][14][15][16] The normal force of the MR materials is the force induced by the forming of chain or cluster structure along the direction of the magnetic eld which is perpendicular to the shear stress. This normal force has signicant impacts on the mechanical performance of MR materials-based devices and is suggested to be considered in the design stage of MR devices.…”

“…23,24 To date, the investigations into the normal force of MR materials are only carried out under limited loading conditions, i.e., static (shear rate< 10 À4 s À1 ) and dynamic (shear rate> 10 À1 /s) loadings. 16,17,21 Researches addressing the normal force of MR grease under quasi-static shear (10 À4 s À1 < shear rate < 10 À1 s À1 ) were rarely reported. For real-life engineering applications of MR grease dampers to civil infrastructures, i.e., building and bridge, MR grease is oen subjected to the combination of large deformation and quasi-static shear loadings.…”