The influence of inducing magnetic field on the magnetoelectric effect of particulate magnetoelectric composites

The magnetoelectric effect in a three-phase particulate magnetoelectric composite is experimentally studied with specific interest in the dependence on the inducing magnetic field up to 300 Oe. A particulate magnetoelectric composite consisting 30 vol% of PVDF, 63 vol% of PZT and 7 vol% of Terfenol-D is fabricated in lab followed by the inducing magnetic field along the diameter direction in the process of hot pressing. It is observed that the change of inducing magnetic field influences the value of the magnetoelectric coefficient. This is partly attributed to the oriented domain walls promote the increase of the magnetostrictive coefficient of Terfenol-D, and partly attributed to the contraction deformation of Terfenol-D which causes the decrease of the coupling coefficient between PZT, TD and PVDF, which together influence the change of the magnetoelectric coefficient. In addition to the inducing magnetic field, the influence of the bias magnetic field in the process of testing to the magnetoelectric coefficient is examined at different fixed resonance frequency. A maximum of magnetoelectric coefficient 82.58 mV/(cm Oe) is obtained when the inducing magnetic field H-i = 200 Oe and the bias magnetic field H-dc = 1000 Oe. When H-i < 200 Oe, the increase of the magnetostrictive coefficient of Terfenol-D plays a leading role which leads to increasing magnetoelectric response. In the H-i range of 200 Oe < H-i < 300 Oe, the decrease of the coupling coefficient between PZT, TD and PVDF plays a leading role and the magnetoelectric coefficient drops along the increase of the inducing magnetic field. (C) 2015 Published by Elsevier B. V.