Ceramics of quasi-binary concentration section ([Formula: see text] = 0.50, 0.1 [Formula: see text] 0.2, [Formula: see text] = 0.025) of the ternary solid solution system (1[Formula: see text]BiFeO3–[Formula: see text][Formula: see text][Formula: see text]O3–[Formula: see text]PbTiO3 were prepared by the conventional solid-phase reaction method. By using X-ray diffraction technique, the phase diagram of the system was constructed, which was shown to contain the regions of cubic and tetragonal symmetry and the morphotropic phase boundary between them. Grain morphology, dielectric and piezoelectric properties of the selected solid solutions were investigated. The highest piezoelectric coefficient [Formula: see text]= 260 pC/N was obtained. Dielectric characteristics of ceramics revealed ferroelectric relaxor behavior, a region of diffuse phase transition from the paraelectric to ferroelectric phase in the temperature range of 350–500 K.

Ceramics of the ternary solid solution system 0.3BiFeO(3)-0.5PbFe(0.5)Nb(0.5)O(3)-0.2PbTiO(3) were prepared by the conventional solid-phase reaction method. It was found that at room temperature the samples had a tetragonal structure, which transformed into a cubic with increasing temperature. The grain structure, dielectric and piezoelectric characteristics of the obtained ceramics were studied. The piezoelectric coefficient d (33) = 260 pC/N was obtained. It was found that this solid solution demonstrated behavior typical for ferroelectric relaxors with a phase transition in the temperature range of 420 - 430 degrees K. An explanation of the observed effects is given.

Samples of quasi-binary section of the ternary system solid solutions (1-x-y)BiFeO3-xPbFe(0.5)Nb(0.5)O(3)-yPbTiO(3) (x = (0.125 horizontal ellipsis 0.275, Delta x = 0.025) and y = 0.10) were prepared by the solid-phase reactions technique followed by sintering using conventional ceramic technology. Grain structure and dielectric properties of (1-x-y)BiFeO3-xPbFe(0.5)Nb(0.5)O(3)-yPbTiO(3) ceramics have been studied. The obtained dielectric characteristics of ceramics revealed the region of diffuse phase transition from the paraelectric to ferroelectric phase in the temperature range 600 divided by 800 K in the high frequency range and dielectric anomaly in the low one.

Abstract x,T-phase diagram of the solid solution of multiferroic PbFe1/2Ta1/2O3 with ferroelectric PbTiO3 for the 0 ≤ x ≤ 0.3 compositional range was plotted for the first time using the data of dielectric, piezoelectric, and Mössbauer studies.

It was found out that compositional ordering degree S of Yb3+ and Nb5+ ions in PbYb1/2Nb1/2O3 ceramics and correspondingly both the temperature and diffusion of antiferroelectric phase transition can be varied within a wide range by means of high-energy mechanical activation. In particular, for the first time disordered PbYb1/2Nb1/2O3 ceramics exhibiting relaxor-like dielectric properties was fabricated without the use of any additives. For the most ordered PbYb1/2Nb1/2O3 samples (S ≈ 0.82), the coexistence of cubic paraelectric and orthorhombic antiferroelectric phases in a temperature range 190–300 °C was revealed.