Nikita Tolstykh

• Voronezh State Technical University

The influence of silicon dioxide on the structure and dielectric properties of ceramic barium titanate was studied. The obtained results show that Si in concentrations up to 1 mol. % enters to the BaTiO3 lattice, forming the BaTi1-xSixO3 solid solution. Doping barium titanate with silicon leads to a decrease in the size of the crystal cell, a sligh...

The dielectric properties of mixed (1-x)BaTiO 3-xSrTiO 3 nanocomposites (x = 0.0; 0.25, 0.50, 0.75, and 1.00), obtained by sintering their initial components for 5 h at a temperature of 1273 K, are studied in the 100-500 K range of temperatures. X-ray analysis performed at room temperature shows the composites are formed by BaTiO 3 (P4mm) and SrTiO...

Dielectric properties of mixed composites based on TGS and nanocrystalline cellulose (1-x)TGS-xnCell composites with x = 0.2; 0.7, and 0.9 (x is the mass fraction of the cellulose) were studied within temperature range of 20 ÷ 120 °C. A smearing of the ferroelectric phase transition and an increase in its temperature in TGS crystallites included in...

The infra-low frequency elastic modulus and the complex dielectric permittivity of vinylidene fluoride trifluoroethylene VDF70/Tr30, are studied within the temperature range of 20 ÷ 140 °C. The experimental results are used to determine the temperature dependence of order parameter η near the Curie temperature (Tc). It is revealed that spontaneous...

A study is made of the dielectric relaxation observed in the ferroelastic phase of submicron SrTiO3. It is shown that the relaxation process is due to interaction between electric charges and the ferroelastic domains. The presence of electromechanical coupling is confirmed by the results from studying the nonlinear dielectric response in a wide ran...

ABSTRACT Influence of thermal treatment in H 2 atmosphere on magnetic and dielectric properties of nanocrystalline BaTiO 3 samples was studied. It was found that increase of the concentration of oxygen vacancies during prolonged annealing in hydrogen leads to a noticeable increase in the diamagnetic response and a decrease in the magnet-ization and...

Samples of a new layered Sr2 +xBi4 −xTi5 −xTaxO18 (х = 0–0.8) perovskite are produced using state-of-the-art ceramic technology. Their dielectric properties are studied at frequencies of 25 Hz–1 MHz in a wide range of temperatures. It is established that a region undergoing a ferroelectric phase transition acquires 1/f α-type polarization noise. An...

The temperature dependences of the dielectric constant and the intensity of the third harmonics are studied at temperatures of 100-470 K for barium titanate, strontium titanate, and a 0.5BaTiO 3-0.5SrTiO 3 blended nanocomposite with an average crystallite size of around 100 nm. Magnetic hysteresis loops are obtained for BaTiO 3 and SrTiO 3 samples...

A family of new solid solutions Bi6Ti3Fe2-xNiхO18 by conventional ceramic technology where x = 0; 0.1; 0.2; 0.3; and 0.4 was obtained. The temperature dependence of the dielectric constant at a frequency of 1 kHz in the temperature range from 25 to 400 °C was studied. A pronounced maximum was observed that is associated with a structural phase tran...

The temperature dependences of the dielectric constant and the intensity of the third harmonics are studied at temperatures of 100-470 K for barium titanate, strontium titanate, and a 0.5BaTiO 3-0.5SrTiO 3 blended nanocomposite with an average crystallite size of around 100 nm. Magnetic hysteresis loops are obtained for BaTiO 3 and SrTiO 3 samples...

A two-stage ceramic technology was used for producing a family of (1-x) BiFeO3 - x MgFe2O4 heterophase systems. The study of the magnetic hysteresis loop revealed the presence of a ferrimagnetic response. The experimentally obtained concentration and temperature dependences of the magnetic permeability made it possible to consider the influence of...

Sr₍₂₊ₓ₎Bi₍₄₋ₓ₎Ti₍₅₋ₓ₎NbₓO₁₈ materials with x = 0.2, 0.4, 0.6, 0.8, and 1 are synthesized. Investigations of the dielectric constant of the samples reveal an increase in the blurring of the phase transition as the share of titanium ions substituted for niobium ions grows. The Burns temperature and the temperature corresponding to the dielectric perm...

The studies of the dielectric properties of the obtained samples revealed the frequency dispersion and significant smearing of the peak of the real part of the permittivity and the dielectric loss tangent, which indicates the relaxor behavior of the material Sr₂.₈Bi₃.₂Ti₄.₂Nb₀.₈O₁₈, which is not characteristic of pure Sr₂Bi₄Ti₅O₁₈ (without substitu...

The purpose of this research is the synthesis of new layered ferroelectrics, with the general formula Sr₍₂₊ₓ₎Bi₍₄₋ₓ₎Ti₍₅₋ₓ₎NbₓO₁₈ where 0 ≤ x ≤ 1 with the structure of Aurivillius Phases (AP), and the establishment of regularities of the influence of the chemical composition and the degree of structural disorder on the physical properties of these...

Investigation of the influence of substitution of titanium cations Ti⁴⁺ for niobium cations Nb⁵⁺ on the occurrence of relaxor properties of layered perovskite with the structure of Aurivillius phases Sr₍₂₊ₓ₎Bi₍₄₋ₓ₎Ti₍₅₋ₓ₎NbₓO₁₈, as well as the smearing of the phase transition in this material. The study was carried out for 0 ≤ x ≤ 1 with a step of...

According to the standard ceramic technology obtained solid solution (x)BiLi₀.₅Sb₀.₅O₃ — (1−x)Na½Bi½TiO₃. In the temperature range from 23 to 500 °C studied the temperature dependence of the real part of permittivity ε' and tan(δ) at frequencies of 1 to 1,000 kHz in a weak measuring field of about 10 V/cm, which bind to the presence in these sample...

A family of new lead-free materials with the general formula BiMe 2/3Sb1/3O3 (Me = Mg, Ni, Co, Zn) have been synthesized using the standard ceramic technology. The temperature dependences of the permittivity ɛ′ have been studied at frequencies from 0.5 to 1000 kHz in the temperature range from 300 to 800 K. At high temperatures, the permittivity ɛ′...

The low-frequency process of dielectric relaxation in the new lead-free compound BiLi0.6W0.4O3 prepared by conventional ceramic technology is studied. The features of dielectric relaxation are discussed in terms of a model of interaction between the domain boundaries and point defects of a crystalline lattice.

The properties of the new lead-free compound BiLi0.6W0.4O3, obtained using ceramic technology, were studied by dielectric and mechanical spectroscopy. The anomalies of internal friction are, along with the elastic and dielectric properties observed experimentally at a temperature of 350°C, related to its structural phase transition. Dielectric and...