Magnetoelectric Transducer Employing Piezoelectric Ceramic/Ferromagnetic Alloy/High-Permeability FeCuNbSiB Composite

Abstract

This feature of rather large magnetoelectric (ME) coupling at the resonance enables the ME composites to possess great ME energy conversion ability. This paper proposes a new type of ME transducer fabricated from the ferromagnetic alloy FeNi-FACE, high-permeability FeCuNbSiB (Fe73.5Cu1Nb3Si13.5B9) and piezoelectric PZT-8H to achieve the strong ME coupling. On one hand, the effective mechanical quality factor (Qm) of the transducer is significantly high because of the high quality factor values of FeNi-FACE, PZT-8H and FeCuNbSiB respectively. On the other hand, FeCuNbSiB acts as the dynamic driver to enhance the effective piezomagnetic coefficient d33 of the FeNi-FACE. A high ME voltage coefficient (MEVC) and a high ME power output can be obtained since the MEVC and power output at resonance strongly depend on the d33 and the Qm. The experimental results show that the strain coefficient of the FeNi-FACE/FeCuNbSiB laminate at resonance achieves 250 nm/A under Hdc = 23 Oe, which is 6.02 times as high as that for a single FeNi-FACE layer. The maximum MEVC at resonance (αr) achieves 4.65 V/Oe, which is 1.6 times larger than that of the previous Terfenol-D/PZT/Terfenol-D (MPM) composite transducer. The new transducer can obtain an output power of 103.7 μW under a resonant excitation Hac = 0.4 Oe, which is ~16 times higher than that of the previous ultrasonic-horn-substrate composite transducer and decreases the size by nearly 75%.