Role of sintering on magneto-electric effect in CuFe1.8Cr0.2O4–Ba0.8Pb0.2Ti0.8Zr0.2O3 composite ceramics

Composition dependent electrical, dielectric, magnetic and magnetoelectric properties of (x)Co0.5Zn0.5Fe2O4+(1−x)PLZT composites

“…The X-ray diffraction patterns of composites reveal that the intensity as well as number of CZFO lines increase with increasing CZFO content in composites. These results are in agreement with literature [12,13]. The lattice constants calculated for all the samples are given in Table 1.…”

Magnetoelectric Coupling Effects in Multiferroic Complex Oxide Composite Structures

“…The initial work on composite multiferroics was developed at the Philips Research Laboratories in the 1970s and was aimed at designing composite ceramics by either exploring the phase stability diagram of the quinary system Fe–Co–Ti–Ba–O to produce an aligned two‐phase composite of ferroelectric BaTiO 3 and magnetic (CoFe 2 O 4 ) 1‐ x (Co 2 TiO 4 ) x oxides,127, 154, 155 or more simply by sintering ferroelectric and ferromagnetic powders to achieve the composite structure 156, 157. The magnetoelectric coupling coefficients characteristic of these composites were larger than those typical of intrinsic multiferroics, in the range from 1–130 mV cm −1 Oe −1 , but the magnetoelectric coupling depended strongly on the exact composition of the magnetic phase, crystallite size, and grain arrangement, giving rise to a large variability in properties 128, 152, 157–159. Other difficulties relate to electrical shunting from the low resistivity magnetic component (limiting the electric field strength used for poling and resulting in the loss of induced voltage);160, 161 residual strain or cracks that may develop during thermal cycling due to thermal expansion mismatch between phases, leading to poor mechanical coupling; the presence of voids and spurious phases; defects in the crystalline structure of each phase, including vacancies and dislocations; variations in crystallite sizes, shapes, and packings, which can reduce the mechanical coupling; deviations from bulk properties, such as reduced magnetic and electric polarizations, reduced magnetostrictive and piezoelectric coefficients, modified magnetic anisotropies, and dielectric response; and the presence of magnetic and ferroelectric domain walls 128, 162–163…”

The physics of magnetoelectric composites

“…The advantages of this route are: simple, cheap and free choice of the composition of the constituents. Using this method, a large amount of ME composites have been prepared such as: CoFe 2 O 4 /PZT [16] [19], etc. However, the composites prepared by this method usually result in a lower ME coefficient if compared to those prepared by other methods [20].…”