Peak divergence in the curve of magnetoelectric coefficient versus dc bias magnetic field at resonance region for bi-layer magnetostrictive/piezoelectric composites

Magnetoelectric (ME) coefficient dependence on the bias magnetic field at resonance frequencies for the bi-layered bonded Terfenol-D/Pb(Zr,Ti)O3 composite was investigated. The resonance frequency decreases first and then increases with the bias magnetic field (HDC), showing a “V” shape in the range of 0 ∼ 5 kOe. Below the resonance frequency, the pattern of ME coefficient dependence on the HDC shows a single peak, but splits into a double-peak pattern when the testing frequency increases into a certain region. With increasing the frequency, a divergent evolution of the HDC patterns was observed. Domain motion and ΔE effect combined with magnetostriction-piezoelectric coupling effect were employed to explain this experimental result.