High sensitivity magnetic sensor consisting of ferromagnetic alloy, piezoelectric ceramic and high-permeability FeCuNbSiB

摘要

A high sensitivity magnetoelectric (ME) composite sensor employing a type of ferromagnetic constant-elasticity alloy (FeNi-FACE), piezoelectric Pb(Zr,Ti)O_3 (PZT-8H) and high-permeability FeCuNbSiB (Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9) is developed. The FeCuNbSiB ribbon with the high permeability serves as the dynamic driver to increase the effective piezomagnetic coefficient d_(33) of the FeNi-FACE. At the same time, the FeCuNbSiB/FeNi-FACE/PZT-8H/FeNi-FACE/FeCuNbSiB (FeFPFFe) composite sensor exhibits a higher effective mechanical quality factor (Qm), which is ～7.7 times higher than that of Terfenol-D/PZT-8H/Terfenol-D (MPM) sensor. As the ME voltage at resonance is directly proportional to the product of piezomagnetic coefficient and Qm. a stronger ME effect can be achieved. The experimental results show that the resonance ME voltage coefficient (MEVC) of the FeFPFFe sensor at H_(dc) = 119 Oe achieves 4.367V/Oe, which is-1.41 times higher than that of FeNi-FACE/PZT-8H/FeNi-FACE (FPF) sensor. Furthermore, ?V_(ME)/?H_(dc) for the FeFPFFe sensor achieves ～22.5mV/Oe at H_(dc) = 31 Oe under resonant drive conditions of Hac = 0.1Oe, which is ～20 times higher than that of the previous reported Terfenol-D/Pb(Zr,Ti)O_3/Terfenol-D composite transducer. Thus the FeFPFFe sensor has highly sensitive ac or dc magnetic field sensing.