Enhancement of capacitive type magnetoimpedance effect in ring-type magnetoelectric transducers vibrator via size-dependent resonance frequency

A magnetically tunable magnetoelectric transducer vibrator made of ring-type Pb(Zr,Ti)O3 (PZT)/Terfenol-D (TDF) composite has been developed. We investigated the size effects of the vibrator resonance frequency. The relative effective permittivity and relative effective permeability of magnetoelectric composite are related to the size of ferromagnetic material. Improvements of about 469%, 176% and 696% of magnetoimpedance, magnetoinductance and magnetocapacitance have been achieved at anti-resonance of the vibrator, respectively. The dramatic change in the magnitude of capacitive type magnetoimpedance, magnetoinductance and magnetocapacitance shows that their responses depend on the size of the magnetostrictive ring in the transducer composite vibrator. The capacitive type magnetoimpedance effect can be substantially enhanced via properly designing the inner radius of magnetostrictive ring, which providing an alternative avenue for increasing magnetically tunable sensitivity.