Composite Magnetoelectric Transducer of Terfenol-D and Pb(Zr,Ti)O $_{3}$ Plates Bonded on an Elastic Substrate

The megnetoelectric (ME) effect of magnetostrictive Terfenol-D (Tb_{1 - x}Dy_xFe_{2 - y}) and piezoelectric Pb(Zr,Ti)O₃ plates bonded on a beryllium bronze substrate is reported. The substrate severs as a frequency determining element and dominates the quality factor (Q _m) of the oscillator. The device can be regarded as a driven damped system. Its resonance occurs at multimodes where the Terfenol-D plate oscillates at frequencies near the allowed frequencies of the substrate, producing a much greater response to finite AC magnetic field input. The theoretical analysis demonstrates that the ME voltage coefficient (alpha_ME) is directly proportional to the factor of gamma = Q _m k _eff ²/(1 - k _eff ²), where k _eff is the effective electromechanical coupling factor. The experimental results show that: (i) there are multiple ME response peaks; (ii) the alpha_ME and Qm are higher than those of the previous reported laminate composites of Terfenol-D and Pb(Zr,Ti)O₃ plates only; and (iii) the factor of gamma is enhanced by the introduction of elastic substrate and the enhancement of alpha_ME is originated from the increase of the factor of gamma .