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 Tb _0.3Dy _0.7Fe _1.92 (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 (α _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 α _V and f _r, respectively, as a result of the reduced eddy-current losses and enhanced non-180 domain-wall motion-induced negative-δE 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 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.