[en] A two-phase magnetoelectric (ME) parallel sandwich was developed by bonding two longitudinally magnetized Terfenol-D/epoxy pseudo-1-3 magnetostrictive composite plates on two longitudinally polarized PZT/epoxy 2-2 piezoelectric composite plates combined longitudinally as a single plate and with their polarization directions arranged in reverse directions. A significantly large ME voltage sensitivity (ME _V ) of 3.1 V/Oe was observed at the resonance frequency of 42.8 kHz under a relatively low bias field of 0.8 kOe. This resonance ME _V was ∼35 times larger than its nonresonance values, showing great promise of using the proposed sandwich in ME conversion devices

[en] Phase transitions in sol–gel-derived (1 − x)(Bi_1_/_2Na_1_/_2TiO_3)-xBaTiO_3 (0  not ≦ x  not ≦ 0.06) solid solutions were investigated via dynamic mechanical, dielectric, and ferroelectric analyses. Structural phase transition was observed from both noncentrosymmetric ferroelectric to nonpolar (antiferroelectric) forms (FE-AFE) at temperatures ranging from ∼120 °C to ∼210 °C, and from antiferroelectric to paraelectric forms (AFE-PE) at temperatures ranging from ∼250 °C to ∼320 °C for 0 ≦ x ≦ 0.06. The former transition is accompanied by a significant and broad elastic softening or soft-mode process, and the latter is of typical diffused type. The dynamic mechanical scaling exponent and critical scaling exponent are used to characterize these two phase transitions, respectively. The temperature-dependent polarization showed an abnormal trend unlike other reported ferroelectrics, confirming the presence of two different phases: FE and AFE. The d_3_3 piezoelectric constant increases with increasing x up to the morphotropic phase boundary. It is suggested that the dynamic mechanical scaling exponents could be used to characterize the mobility of the polar domains and the elastic softening processes, which are closely related to abnormal pyroelectric properties and piezoelastic hardening behaviors. (paper)