In this paper, on the basis of the viscoelastic fractional derivative model, Mittag-Leffler function is applied to deduce the expression of stress relaxation modulus for magnetorheological elastomers according to its form and main properties. Furthermore, the relaxation modulus for polyurethane rubber matrix cured magnetorheological elastomers at different applied magnetic fields and shear strains is tested by rheometer. The results indicate that magnetorheological elastomers exhibit obvious relaxation behavior and the magnetic field strength and shear strain exert significant influence on the relaxation behavior: the relaxation modulus of magnetorheological elastomers increases with the magnetic field strength but decreases with the shear strain. Besides, the model agrees well with the experimental data which indicates that the model is suitable for characterization of relaxation behavior for magnetorheological elastomers.
Effect of magnetic field strength on plastic scintillation detector response