Hysteresis and loss characteristics of metal rubber damper based on improved Preisach model

In this study, a new hysteresis mechanical model of metal rubber was developed based on the magnetic flux change of metal rubber damper after cyclic loading and the subsequent static stiffness degradation This new model aims to overcome the shortcomings of the traditional high-order friction theory hysteresis model in explaining the stiffness fluctuation and temperature magnetic flux change of the shock absorber. Through the large load cyclic loading experiment of the metal rubber damper, the hysteresis characteristics of the metal rubber damper without fatigue fracture were ana-lyzed in depth. Based on the electromagnetic theory and the force and displacement constitutive relationship of the metal rubber, the Preisach mechanical hysteresis model was established. The experimental test outcomes were substituted into the model for parameter identification and the model was modified as necessary. Compared to the traditional dynamic hysteresis model based on power series and elliptic equation, the Preisach model showed higher accuracy in simulating the energy dissipation and damping ratio of the experimental data of the shock absorber. The error was controlled within 2 %. Especially in the abrupt region of the unloading curve, the nonlinear stiffness error of the Preisach model was determined to be only half of that of the traditional model. The Preisach mechanical hysteresis model deeply explores the microscopic electromagnetic characteristics of the metal rubber damper, thus revealing the internal mechanism of its hysteresis change. This model can not only accurately simulate the sudden change of the curve of the shock absorber during the unloading process, but also make the model prediction closer to the actual application scenario through the highly simulated simulation results.