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Passive adaptive MR damper is a new type of damper based on GMM inverse effect and MR effect, and it doesn’t need energy devices and can realize external force self-adaptation. A model of passive adaptive MR damper is established based on Jiles-Atherton model, the law of approach for the magnetomechanical effect, the magnetic circuit law and Bingham model. Experimental results show that the value of damping force is related to displacement and velocity: the larger the displacement, the greater the damping force; the faster the speed, the greater the damping force. This is consistent with the model.

In the current paper, the rate dependent hysteretic dynamics of a magnetostrictive transducer is investigated by using a coupled nonlinear macroscopic differential model. The transducer is modeled as a one-dimensional magnetostrictive structure based on the Landau phenomenological theory of phase transition. The hysteresis loops and butterfly-shaped behaviors in the magnetic and mechanical fields are both successfully modeled with estimated model parameter values. The capability of the proposed model for capturing the driving rate dependency is illustrated by numerical experiments.

The T(0,1) mode guided wave is widely used in long term NDT of the pipelines. The magnetostrictive transducer for generating and detecting guided wave is important to long term NDT of the pipelines because the transducer is compact and can be used at high temperature. The paper explains the mechanism of the generation and detection of T(0,1) mode guided wave in magnetostrictive strip based on Wiedemann effect. The experiment with MSGW is done to confirm the mechanism in a aluminum pipe.