Magnetoelectric properties of Tb0.27−xDy0.73−yYx+yFe2/PVDF composites

Highlights: ► New intermetallic series and magnetoelectric composites were prepared. ► The contributions to total resistivity were separated for the Tb0.27−xDy0.73−yYx+yFe2 series. ► Magnetoelectric voltage coefficient for composites exceeds 8 mV/(cm Oe). ► ME coefficient of composites reduces along with the yttrium content in the intermetallic compound. - Abstract: Synthesis by arc melting, and the structural and electric properties of yttrium-diluted Tb0.27−xDy0.73−yYx+yFe2 intermetallics were studied by X-ray diffraction (XRD) and four-probe dc electrical measurements. XRD analysis (300 K) shows that all samples crystallize in a cubic, Fd3m, MgCu2-type structure. The lattice parameter increases along with the yttrium content. Electrical resistivity for the Tb0.27−xDy0.73−yYx+yFe2 intermetallic series was measured in a temperature range of 15–1100 K. The parameters involved in the dependence of resistivity on temperature were determined. Residual, phonon and magnetic resistivity were separated from the measured electrical resistivity using both the Matthiesen formula and the Bloch–Grűneisen formula. Curie temperatures of the compounds were obtained from the magnetic resistivity curves. Magnetoelectric composites containing magnetostrictive Tb0.27−xDy0.73−yYx+yFe2 grains in a PVDF matrix were prepared. All the composites were characterized by scanning electron microscope observations. The measurements carried out at room temperature as a function of the external DC magnetic field and frequency of the sinusoidal AC modulation magnetic field reveal a distinct magnetoelectric effect of the Tb0.27−xDy0.73−yYx+yFe2/PVDF composites.