Твердофазным синтезом с последующим спеканием по обычной керамической технологии получены образцы твердых растворов трехкомпонентной системы (1-x)Pb(Ti0.5Zr0.5)O3- x/2CdNb2O6 с x=0.025÷0.100, Δx=0.025. Исследованы кристаллическая структура, микроструктура, электрофизичские и теплофизические свойства этих керамик. Показано, что все исследованные твердые растворы можно разделить на две группы (с x=0.025 и с x>0.025), характеризующиеся различными особенностями изменения свойств при вариациях внешних воздействий.Это, вероятно, обусловлено переходом отструктуры типа перовскита с тетрагональной (Т) элементарной ячейкой к неоднородным ТР, состоящим из серии Т- фаз с близкими параметрами ячейки. Сделано заключение о целесообразности использования полученных данных при разработке подобных материалов устройств на их основе.

Using the method of two-stage solid-phase synthesis, involving mechanical activation of the synthesized powders and subsequent sintering using conventional ceramic technology, ferroelectric multicomponent solid solutions, based on the PZT system, were produced, characterized by fairly high Curie temperatures and pyroelectric coefficients, high coefficients of pyroelectric sensitivity and resistance to vibration interference, which makes it possible to classify them as pyroelectric materials, are promising for use as working elements of sensors for pyroelectric receivers of radiant (thermal) energy.

We studied solid solutions of the system (1-x)PbFe1/2Nb1/2O3 - xPbFe(2/3)W(1/3)O(3) using X-ray and Neuron diffraction, and M & ouml;ssbauer spectroscopy. To obtain ceramics, we used the method of two-stage solid-phase synthesis and sintering according to the conventional ceramic technology. Pure solid solutions of the (1-x)PbFe1/2Nb1/2O3-xPbFe(2/3)W(1/3)O(3) system were obtained. A deviation of the unit cell parameters from the Vegard rule was revealed, which indicates stratification of the structure into microregions differing in composition. The introduction of PbFe2/3W1/3O3 into the system led to partial ordering (clustering) of cations in the B position. An increase in magnetic moment with growing amount of PbFe2/3W1/3O3 was shown.

For the first time, ceramic solid solutions of the five-component system 1-x)(0.5(Na0.5K0.5)NbO3-0.5Pb (Zr0.5Ti0.5)O3)-x/2CdNb2O6 with concentrations of CdNb2O6 x = 0.000; 0.025; 0.050; 0.075 were prepared. Experimental studies of crystalline and grain structure, dielectric, piezoelectric and ferroelastic properties have been carried out over a wide temperature range. X-ray diffraction data were used to construct a concentration diagram of the phase states and to establish correlations between the behaviour of the macroproperties of the solid solutions and the features of their crystal structure. A conclusion is made about the expediency of using the obtained results in the creation of similar materials and devices based on them.

The solid solutions of the (1 – х)BiFeO3–x/2PbFe1/2Nb1/2O3–x/2PbFe2/3W1/3O3 system in the concentration range 0.05 ≤ х ≤ 0.50 were produced by solid state method and sintering using conventional ceramic technology. In the range 0.25 x 0.35, a morphotropic phase transition from the rhombohedral phase to the cubic phase was found. The difference in symmetry when “scaling” the material is shown. The influence of PbFe1/2Nb1/2O3 and PbFe2/3W1/3O3 on the grain structure formation was established.

Results of studies of the structure, microstructure, dielectric characteristics and the Mossbauer effect of solid solutions of the (1-x)PbFe1/2Nb1/2O3 -xPbFe2/3W1/3O3 system in wide temperature range are pre-sented. X-Ray diffraction and Mossbauer spectra showed that in the PbFe1/2Nb1/2O3 there are regions with a high and low concentration of Fe3+ ions -clustering; in PbFe2/3W1/3O3 there is a process of local ordering of cations in the B-sublattice. The number of local states of Fe3+ ions indicates the occurrence of partial or-dering of ions in the B-position in the system (1-x)PbFe1/2Nb1/2O3 -xPbFe2/3W1/3O3. As x concentration increases, a nearly linear increase in the N e el temperature was observed. Investigation of ceramic cleavage surfaces allows us to conclude that the grain structure and the dependence of the grain size on the amount of the PbFe2/3W1/3O3 are inhomogeneous. It is shown that additional maxima in the dependence of the imaginary part of relative complex permittivity appearing above the phase transition temperature are as-sociated with the onset of hopping conduction. (c) 2022 Elsevier B.V. All rights reserved.

Conventional ceramic technology is used to obtain impurity-free (1 – х)BiFeO3–x/2PbFe1/2Nb1/2O3–x/2PbFe2/3W1/3O3 (0.05 ≤ х ≤ 0.50) solid solutions via solid-state synthesis and sintering. A morphotropic transition from the rhombohedral to the cubic phase is observed in the 0.25 < x < 0.35 range of concentrations. The difference in symmetry upon scaling the material is shown. The effect PbFe1/2Nb1/2O3 and PbFe2/3W1/3O3 have on the formation of the grain structure is established.

Conventional ceramic technology is used to obtain impurity-free (1 – х )BiFeO 3 – x /2PbFe 1/2 Nb 1/2 O 3 – x /2PbFe 2/3 W 1/3 O 3 (0.05 ≤ х ≤ 0.50) solid solutions via solid-state synthesis and sintering. A morphotropic transition from the rhombohedral to the cubic phase is observed in the 0.25 < x < 0.35 range of concentrations. The difference in symmetry upon scaling the material is shown. The effect PbFe 1/2 Nb 1/2 O 3 and PbFe 2/3 W 1/3 O 3 have on the formation of the grain structure is established.

Atomic ordering in many perovskites can be controlled by suitable synthesis conditions or annealing at elevated temperatures and is yet another phenomenon that can be used to manipulate their properties. In this work we have synthesized low impurity high quality medium-entropy ceramics of PbSc1/4In1/4Nb1/4Ta1/4O3 (PSINT), which can be formally represented as a solid solution of PbSc1/2Nb1/2O3 (PSN), PbSc1/2Ta1/2O3 (PST), PbIn1/2Nb1/2O3 (PIN), and PbIn1/2Ta1/2O3 (PIT) – the perovskites exhibiting atomic order–disorder phenomena. PSINT ceramics reveals pronounced dielectric maximum and a relaxor behavior. Estimation of the atomic order–disorder phase transition temperature by Monte-Carlo calculations shows that for PSINT it should fall within the same range as for PSN, PST, PIN, and PIT. Prolonged annealing of PSINT at the corresponding temperatures indeed results in clear changes in the dielectric behavior but does not lead to noticeable differences in the X-ray powder diffraction that could be interpreted as appearance of atomic ordering.

The solid solutions (SS) of the n-component (n = 2 ... 6) systems with the participation of two fundamentally different bases - (Na, K)NbO3 (NKN) and Pb(Ti, Zr)O3 (PZT) have been prepared by the two-stage solid-phase synthesis followed by the conventional sintering ceramic technology. Evolution trends of the structural and electrophysical parameters at such a complication of the compositions have been established. It is shown that with an increase in the number of the components in the systems, the spontaneous deformation, characterized by a uniform deformation parameter, delta, decreases, which, due to the existing correlations, leads to a decrease in the Curie temperature and an increase in the relative permittivity. The extreme "behavior" of the piezoelectric characteristics is associated with the competing influence of the permittivity and remanent polarization on them. A conclusion is made about the expediency of using the obtained results in the creation of similar materials and devices based on them.

The solid solutions of the (1-x)BiFeO3 - x/2PbFe(1/2)Nb(1/2)O(3) -x/2PbFe(2/3)W(1/3)O(3) system (x = 0.05, x = 0.50) were produced by conventional solid state technology using mechanical activation (MA). It is discovered that particle destruction occurs along planar defects (crystallographic shear planes, CSP) during MA. The MA has a different impact on the microstructure formation of the solid solutions (1-x)BiFeO3 - x/2PbFe(1/2)Nb(1/2)O(3) - x/2PbFe(2/3)W(1/3)O(3) system, depending on their localization on the phase diagram. It is shown that MA leads to an increase in the temperature stability of the dielectric properties in the solid solutions of the studied system.

The solid solutions of the (1 – х)BiFeO3–x/2PbFe1/2Nb1/2O3–x/2PbFe2/3W1/3O3 system in the concentration range 0.05 ≤ х ≤ 0.50 were produced by solid state method and sintering using conventional ceramic technology. In the range 0.25 x 0.35, a morphotropic phase transition from the rhombohedral phase to the cubic phase was found. The difference in symmetry when “scaling” the material is shown. The influence of PbFe1/2Nb1/2O3 and PbFe2/3W1/3O3 on the grain structure formation was established.

Atomic ordering in many perovskites can be controlled by suitable synthesis conditions or annealing at elevated temperatures and is yet another phenomenon that can be used to manipulate their properties. In this work we have synthesized low impurity high quality medium-entropy ceramics of PbSc1/4In1/4Nb1/4Ta1/4O3 (PSINT), which can be formally represented as a solid solution of PbSc1/2Nb1/2O3 (PSN), PbSc1/2Ta1/2O3 (PST), PbIn1/2Nb1/2O3 (PIN), and PbIn1/2Ta1/2O3 (PIT) - the perovskites exhibiting atomic order-disorder phenomena. PSINT ceramics reveals pronounced dielectric maximum and a relaxor behavior. Estimation of the atomic order-disorder phase transition temperature by Monte-Carlo calculations shows that for PSINT it should fall within the same range as for PSN, PST, PIN, and PIT. Prolonged annealing of PSINT at the corresponding temperatures indeed results in clear changes in the dielectric behavior but does not lead to noticeable differences in the X-ray powder diffraction that could be interpreted as appearance of atomic ordering.

The paper reports results on the complex study on ferroelectric ceramics that represent solid solutions containing components with a perovskite-type or columbite-type structure. Solid solutions of a three-component (1[Formula: see text])[Formula: see text][Formula: see text]CdNb2O6 system are manufactured at [Formula: see text] = 0.05–0.20 and [Formula: see text] = 0.10. Domain structures in ceramic grains are studied. The consistency between experimental and calculated results is examined for coexisting phases split into non-180[Formula: see text] domains (mechanical twins) in the solid solution with [Formula: see text] = 0.15. A correlation between the internal structure (crystal, domain, granular, and defect) and fundamental electromechanical and polarization properties is stated for the studied three-component solid solutions.

High-strength ferroelectric materials based on a multicomponent system with the presence of the PZT, characterized by a high Curie temperature, TC, the increased sensitivity to mechanical stress, and long-term stability, were manufactured with help of by the two-stage solid-phase synthesis followed by sintering using the conventional ceramic technology. Based on the studies of the dielectric properties in the temperature range of (300-800)K, the frequencies of the alternating electric field (25-2 x 106)Hz of AC field were found, and the features of the observed dispersion phenomena were revealed. It was shown that these materials also have stable piezoelectric properties over a wide temperature range. A conclusion about the expediency of using the obtained data in the development of accelerometers, ultrasonic flaw detectors, nondestructive testing devices, etc. with similar materials has been made.

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 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.

This paper presents a study of microstructure and dielectric properties of solid solutions of (1-x)BiFeO3 - x/2 PbFe1/2Nb1/2O3 - x/2 PbFe2/3W1/3O3 system with x = 0.05 divided by 0.50 using X-ray diffraction analysis. Phase diagram of the studied system at room temperature is obtained. Critical influence of oxygen defects and liquid phase on formation of structure and microstructure of the samples is detected. Relaxor nature epsilon ''/epsilon(0) for the studied solid solutions is demonstrated dealing with occurrence of Maxwell-Wagner's relaxation due to movement of oxygen vacancies.

Solid solutions of the composition Ba[Formula: see text](Mg, Ln)[Formula: see text][Formula: see text]TiO 3 ([Formula: see text] = 0.01; 0.025; 0.04; [Formula: see text] = 0.20; 0.50; 0.80; Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tu, Yb) were prepared by two-stage solid-phase synthesis followed by sintering using conventional ceramic technology. The influence of rare-earth elements on the microstructure of the prepared ceramic samples was investigated. It was found that regardless of the type of modifiers introduced, the grain landscape of the studied solid solutions with different amounts of SrTiO 3 is refined (in the initial system, the average grain size, [Formula: see text], at [Formula: see text] = 0.20 is 6 [Formula: see text]m; at [Formula: see text] = 0.50 is 4 [Formula: see text]m; at [Formula: see text] = 0.80 is 18 [Formula: see text]m) to crystallite sizes not exceeding (2-3) [Formula: see text]m, and compacted. The using of mechanical activation procedures leads to an even greater decrease in the size and an increase in the density of ceramics. The increasing in the concentration of modifiers in each group (within the considered range of dopant variation) against the background of such a fine-grained structure has little effect on the dynamics of changes in [Formula: see text]. It is concluded that it is advisable to use the data obtained in the development of functional materials based on BST/(Mg, Ln) and devices with the participation of these compositions.