Effect of adjustable bias voltage on magnetoelectric properties of magnetostrictive/piezoelectric laminated transducer structure

The magnetoelectric properties of PZT5/Terfenol-D/PZT8 laminated transducer structure are analyzed and detected for adjusting the bias voltage across PZT5. A control method of one-order resonant frequency for a magnetostrictive/piezoelectric laminated magnetoelectric transducer structure is proposed. The resonant frequency and the prestrain of the magnetoelectric laminated structure can be adjusted by changing the bias voltage across PZT5. The relationships between the control voltage, the strain, the Young's modulus, the resonant frequencies and the resonant magnetoelectric coefficient are analyzed. Theoretical analyses show that the resonant frequency of the laminated structure is almost a linear function of the applied dc bias voltage at a small strain. The magnetoelectric coefficient is hardly related to the control voltage. The experimental results verify the theoretical analyses. For a control voltage of -170 V to +170 V, the resonant frequency can be linearly adjusted. The adjusted maximum of the resonant frequency is 1 kHz. The ratio of the adjusted value to the bias control voltage is 2.94 Hz/V. For a bias magnetic field from 0 Oe to 225 Oe, the resonant frequency is almost unrelated to the bias magnetic field. The magnetoelectric voltage coefficient changes with the bias magnetic field. A maximum magnetoelectric voltage coefficient of 1.65 V/Oe is obtained at a bias magnetic field of > 178 Oe.