Features of the Structure and Electrophysical Properties of Solid Solutions of the System (1-x-y) NaNbO3-xKNbO3-yCd0.5NbO3

Ferroelectric ceramic materials based on the (1-x-y) NaNbO3-xKNbO3-yCd0.5NbO3 system (x = 0.05–0.65, y = 0.025–0.30, Δx = 0.05) were obtained by a two-stage solid-phase synthesis followed by sintering using conventional ceramic technology. It was found that the region of pure solid solutions extends to x = 0.70 at y = 0.05 and, with increasing y, it narrows down to x ≤ 0.10 at y = 0.25. Going out beyond the specified concentrations leads to the formation of a heterogeneous region. It is shown that the grain landscape of all studied ceramics is formed during recrystallization sintering in the presence of a liquid phase, the source of which is unreacted components (Na2CO3 with Tmelt. = 1126 K, K2CO3 with Tmelt. = 1164 K, KOH with Tmelt. = 677 K) and low-melting eutectics in niobate mixtures (NaNbO3, Tmelt. = 1260 K, KNbO3, Tmelt. = 1118 K). A study of the electrophysical properties at room temperature showed the nonmonotonic behavior of all dependences with extrema near symmetry transitions, which corresponds to the logic of changes in the electrophysical parameters in systems with morphotropic phase boundaries. An analysis of the evolution of dielectric spectra made it possible to distinguish three groups of solid solutions: classical ferroelectrics (y = 0.05–0.10), ferroelectrics with a diffuse phase transition (y = 0.30), and ferroelectrics relaxors (y = 0.15–0.25). A conclusion about the expediency of using the obtained data in the development of materials and devices based on such materials has been made.

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Thermal expansion of solid solutions of the Pb(Zr,Ti)O3 system near lead zirconate

Journal of Physics Conference Series ◽

10.1088/1742-6596/2057/1/012060 ◽

2021 ◽

Vol 2057 (1) ◽

pp. 012060

Author(s):

K P Andryushin ◽

I N Andryushina ◽

L A Shilkina ◽

L A Reznichenko

Keyword(s):

Thermal Expansion ◽

Solid Solutions ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Structural Parameters ◽

Ceramic Materials ◽

Ferroelectric Ceramic ◽

Lead Zirconate ◽

Ceramic Technology ◽

Phase Synthesis

Abstract Ferroelectric ceramic materials based on the Pb(Zr,Ti)O3 (PZT) system were obtained by two-stage solid-phase synthesis followed by sintering using conventional ceramic technology. On the basis of the studies correlations between the thermal expansion and structural parameters of the investigated solid solutions were established. It was concluded that the obtained data are recommended to be used in the development of devices based on solid solutions with the participation of the PZT system.

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Microstructure features of the BST/(Mg, Ln)-ceramic

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21600055 ◽

2021 ◽

pp. 2160005

Author(s):

K. P. Andryushin ◽

A. V. Nagaenko ◽

S. V. Khasbulatov ◽

L. A. Shilkina ◽

E. V. Glazunova ◽

...

Keyword(s):

Solid Solutions ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Functional Materials ◽

Ceramic Technology ◽

Phase Synthesis ◽

Fine Grained ◽

Average Grain Size ◽

Crystallite Sizes ◽

Fine Grained Structure

Solid solutions of the composition Ba[Formula: see text](Mg, Ln)[Formula: see text]Sr[Formula: see text]TiO3 ([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 SrTiO3 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.

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Anomalous Thermal Expansion in Solid-Phase Synthesis of Piezoceramic Material Based on Solid Solutions of Potassium and Sodium Niobates

Glass and Ceramics ◽

10.1007/s10717-018-0012-y ◽

2018 ◽

Vol 74 (11-12) ◽

pp. 440-443

Author(s):

S. G. Ponomarev ◽

V. P. Tarasovskii ◽

V. V. Rybal’chenko ◽

V. I. Koshkin ◽

A. A. Vasin ◽

...

Keyword(s):

Thermal Expansion ◽

Solid Solutions ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Phase Synthesis ◽

Piezoceramic Material ◽

Anomalous Thermal Expansion

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Destruction phenomena in ferroactive materials

Journal of Advanced Dielectrics ◽

10.1142/s2010135x20500125 ◽

2020 ◽

Vol 10 (04) ◽

pp. 2050012

Author(s):

Sidek Khasbulatov ◽

Aleksander Cherpakov ◽

Ivan Parinov ◽

Konstantin Andryushin ◽

Lidiya Shilkina ◽

...

Keyword(s):

Solid Phase ◽

Bismuth Ferrite ◽

Structural Features ◽

Strength Properties ◽

Ceramic Technology ◽

Grain Structure ◽

Structural Elements ◽

Phase Synthesis ◽

Local Stresses ◽

Comprehensive Study

The results of a comprehensive study of the crystal structure, grain structure, and strength properties of ceramic bismuth ferrite with rare earth elements (REE) obtained by two-stage solid-phase synthesis followed by sintering using conventional ceramic technology are presented. The reasons for the formation of low mechanical strength and the development of destruction phenomena in solid solutions with small REE ([Formula: see text] Å) are considered: Tb, Dy, Ho, Er, Tm, Yb, Lu. The causes of the observed phenomena associated with the composite-like structure of the studied media and, as a consequence, the occurrence of local stresses of structural elements that provoke crack formation are established. A source of the latter are also the structural features of the grain landscape. The conclusion is made about the appropriateness of taking into account the information obtained when developing devices based on BiFeO3/REE multiferroics.

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Solid-phase synthesis of solid solutions in Cu/Ni(001) epitaxial nanofilms

JETP Letters ◽

10.1134/s0021364008200101 ◽

2008 ◽

Vol 88 (8) ◽

pp. 515-519 ◽

Cited By ~ 8

Author(s):

V. G. Myagkov ◽

L. E. Bykova ◽

G. N. Bondarenko ◽

V. S. Zhigalov

Keyword(s):

Solid Solutions ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Phase Synthesis

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Using of mechanoactivation for preparation of cerium-containing solid solutions based on zircon

Transaction Kola Science Cetnre ◽

10.37614/2307-5252.2021.2.5.013 ◽

2021 ◽

Vol 12 (2-2021) ◽

pp. 66-71

Author(s):

V. Yu. Vinogradov ◽

◽

A. M. Kalinkin ◽

V. Ya. Kuznetsov ◽

◽

...

Keyword(s):

Solid Solutions ◽

Zirconium Oxide ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Planetary Mill ◽

Molar Ratio ◽

Phase Synthesis ◽

X Ray ◽

Cerium Content ◽

Zircon Structure

Solid-phase synthesis of cerium-containing solid solutions based on ZrSiO4 was described. The synthesis was carried out using mechanical activation of a mixture consisting of zirconium oxide and hydrated amorphous silica with the addition of cerium oxide at a molar ratio of ZrО2:SiО2:CeО2 equal to 0.95:1.00:0.05. The mechanically activated in a centrifugal planetary mill mixture of reagents was calcined in the temperature range of 1200–1600 °C for 3 hours, which was accompanied by the essentially complete synthesis of zircon. The cerium content in the zircon structure was calculated from X-ray powder diffraction data.

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