High magnetoelectric tuning effect in a polymer-based magnetostrictive-piezoelectric laminate under resonance drive

A polymer-based magnetoelectric (ME) laminate was fabricated by sandwiching one layer of thickness-polarized, length-stretched polyvinylidene fluoride (PVDF) piezoelectric polymer between two layers of length-magnetized, epoxy-bonded Tb0.3Dy0.7Fe1.92 (Terfenol-D) pseudo-1-3 magnetostrictive particulate composite in the thickness direction, and its resonance ME effect was investigated, both experimentally and theoretically, as a function of magnetic bias field (H-Bias). The laminate showed a high ME voltage coefficient (alpha(V)) of 233 mV/Oe at the fundamental resonance frequency (f(r)) of 60.6 kHz under a relatively low H-Bias of 0.6 kOe. By controlling H-Bias in the range of 0.02-1.5 kOe, nonlinear tunabilities as high as 1382 and 8.6% were achieved for alpha(V) and f(r), respectively, as a result of the reduced eddy-current losses and enhanced non-180 degrees domain-wall motion-induced negative-Delta E effect in the Terfenol-D composite layers as well as the increased compliance contribution from the PVDF polymer layer to allow the motion of non-180 degrees domain walls in the Terfenol-D composite layers. This improved resonance ME tuning effect, together with the durable and tailorable natures, makes the laminate great promise for developing into tunable ME devices. (C) 2012 American Institute of Physics. [doi:10.1063/1.3678321]