Magnetoelectric Effect in Two-Layer Composites with a Graded Magnetic Phase

Samples of a homogeneous ( x = 0, 0.1, and 0.2) and multilayer ceramics with a gradient composition ( x = 0.2 → 0.1 → 0 → 0.1 → 0.2) based on solid solutions of (Ni 1 − x Zn x )Fe 2 O 4 nickel–zinc ferrites have been manufactured using the thick-film technology. After sintering in a two-step mode, the gradient samples exhibited a smooth non-uniform distribution of chemical elements (Zn, Ni) over the thickness. The longitudinal (α E 33 ) and transverse (α E 31 ) magnetoelectric effects in two-layer PZT–nickel ferrite composites have been studied. In the absence of an external magnetostatic field, the values of magnetoelectric coefficients were negligible. The maximum value of the longitudinal magnetoelectric coefficient for composites with the gradient magnetic phase was practically two times higher than value of α E 33 for homogeneous structures.