Near-flat self-biased magnetoelectric response in three-phase METGLAS/TERFENOL-D/ PZT laminated composites

In this study, three-phase laminated composite with high-permeability Metglas 2605 S2 (FeSiB) ribbon, giant magnetostrictive material Terfenol-D and Piezoelectric ceramics PZT8 are investigated . The internal magnetic field induced by the differences in magnetic properties of Terfenol-D and Metglas and the stress coupling effect between Terfenol-D and Metglas contributes to the self-biased ME effect with a wide range of dc bias response . The Metglas features with excellent magnetic permeability (10000 at f= 1 kHz) and low coercive field (Hc = 21 .03 Oe), compared with Terfenol-D . The Metglas and Terfenol-D forms a magnetization-graded ferromagnetic layer, which results in a strong internal magnetic bias and leads to a high dynamic piezomagnetic coefficient d33 at zero bias due to the Hdc dependence of the d33 . The dynamic piezomagnetic coefficients d33 for the magnetization-graded ferromagnetic layer Terfenol-D/Metglas as a function of numbers of Metglas layer L at zero bias is measured by Doppler vibrometer. It is found that the Terfenol-D/Metglas exhibits a much larger d33 at zero bias compared to the single layer of Terfenol-D (L=0) . When L=3, the dynamic piezomagnetic coefficient for Terfenol-D/Metglas reaches the maximum value (41 .9 nm/A) at zero bias.