EFFECT OF MODIFYING ZIRCONIUM OXIDE ADDITIVE ON THE PROPERTIES OF CERAMIC MATERIALS OF THE Y2O3–Al2O3–SiO2 SYSTEM OBTAINED BY THE SOL-GEL METHOD

2021 ◽  
pp. 67-78
Author(s):  
Yu.E. Lebedeva ◽  
◽  
N.E. Shchegoleva ◽  
V.A. Voronov ◽  
V.S. Kovaleva ◽  
...  
Keyword(s):  
Zirconium Oxide ◽  
Sol Gel ◽  
Ceramic Materials ◽  
Tetragonal Modification ◽  
Gel Method ◽  
Sio2 System ◽  
Sol Gel Method ◽  
Zirconium Silicate ◽  
Main Crystalline Phase ◽  
Modifying Additive

The effect of the modifying additive ZrO2 on the rheological properties, the processes of structure and phase formation of the compositions of the Y2O3–Al2O3–SiO2 system obtained by the sol-gel method has been investigated. It was found that the temperature range of crystallization of the compositions of the Y2O3–Al2O3–SiO2 system with the addition of ZrO2 is 1020–1270 °C and with an increase in the concentration of zirconium oxide, the amount of the main crystalline phase of yttrium pyrosilicate (β-Y2Si2O7) decreases and the concentration of the zirconium-containing phase – the tetragonal modification of zirconium oxide and zirconium silicate ZrSiO4 -increases.

scholarly journals Sol - gel method for producing of glass binding in the Li2O - Al2O3 - SiO2 system for ceramic materials

2020 ◽  
Vol 120 ◽  
pp. 186-195
Author(s):  
E. S. Khomenko ◽  
E. V. Karasik
Keyword(s):  
Thermal Expansion ◽  
Low Temperature ◽  
Sol Gel ◽  
Ceramic Materials ◽  
Aluminum Silicate ◽  
Charge Composition ◽  
Gel Method ◽  
Sio2 System ◽  
Sol Gel Method ◽  
Quartz Ceramics

The results of glass binding obtaining in the Li2O — Al2O3 — SiO2 system for ceramic materials are presented in the article. The lithium aluminum silicate system was chosen taking into account the low temperature expansion coefficients of crystalline phases that form in it. This will allow controlling the thermal expansion of materials into which the glass binding will be introduced. A sol - gel method based on ethyl silicate and soluble salts of the corresponding oxides is proposed as a method for producing of glass binding. This method is more rational in comparison with the traditional method of glass melting due to low energy costs. Also, the method allows to obtain a more uniform and active product. The effect of glass binding on the properties of ceramic materials for various purposes has been investigated. As such materials, low-temperature electrotechnical porcelain, quartz ceramics, and engobe coatings were chosen. The glass binding was introduced into the raw material charge of these materials in an amount of 5 wt. %. Further, the properties of calcined product without additives and with additives under the same conditions were compared. The intense fluxing effect of glass binding during the formation of electrical porcelain has been established. The glass binding reinforces the effect of natural fluxes (pegmatites) that are present in the basic composition of the mass. This contributes to the material compaction during firing. The formation of eucryptite and spodumene helps to reduce the thermal expansion of material. The introduction of glass binding into the engobe led to a less intense compaction of its structure. This was observed due to an insufficient amount of the added glass binding for this type of material. In the composition of quartz ceramics, glass binding contributed to the material sintering, but the thermal properties were deteriorated. Thus, the sintering results of ceramic material with the introduction of glass binding in the charge composition are positive. However, sintering significantly depends on the material type. The glass binding stimulates the formation of a melt in which solid finely dispersed components of the ceramic mass dissolve. This contributes to the formation of a dense durable ceramic.

scholarly journals Ceramic Materials. Preparation and Properties of ZrO2-Coated BaTiO3 Composite Particles by Sol-Gel Method with Zr-Alkoxide.

2001 ◽  
Vol 50 (6) ◽  
pp. 630-633 ◽  
Author(s):  
Takashi HAYASHI ◽  
Akihiro TANIMURA ◽  
Hiroshi SHINOZAKI ◽  
Kazuya TAKANASHI ◽  
Hideyuki AOKI ◽  
...  
Keyword(s):  
Sol Gel ◽  
Ceramic Materials ◽  
Composite Particles ◽  
Gel Method ◽  
Sol Gel Method ◽  
Materials Preparation

Al2O3 AND ZrO2 CERAMIC MATERIALS OBTAINED BY SOL-GEL METHOD

2021 ◽  
pp. 61-73
Author(s):  
Yu.E. Lebedeva ◽  
◽  
N.E. Shchegoleva ◽  
V.A. Voronov ◽  
St.S. Solntcev ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Zirconium Dioxide ◽  
Monoclinic Phase ◽  
Eutectic Composition ◽  
Sol Gel ◽  
Ceramic Materials ◽  
Gel Method ◽  
Sol Gel Method ◽  
Zro2 System ◽  
Sintered Materials

The rheological properties, processes of structure and phase formation of the Al2O3–ZrO2 system compositions obtained by the sol-gel method have been investigated. The temperature range of crystallization of the compositions is 900–1100 °C. With an increase in the concentration of zirconium dioxide in the system, the temperature of the transition from the tetragonal to the monoclinic phase decreases. The effect of the ratio of the components in the initial solutions and the temperature regime of heat treatment of gels on the physicochemical properties of nanopowders and sintered materials has been studied. Ceramic materials of eutectic composition give the highest density and lower values of porosity and water absorption.

EFFECTS OF CONCENTRATION OF TTIP PRODUCER AGENT ON ZrO2/NANOTiO2 POWDER SYNTHESIS

2008 ◽  
Vol 22 (18n19) ◽  
pp. 3216-3224
Author(s):  
E. MOHAMMADI ◽  
H. ABDIZADEH ◽  
H. R. BAHARVANDI ◽  
A. M. HADIAN
Keyword(s):  
Composite Powder ◽  
Mixed Oxides ◽  
Sol Gel ◽  
Ceramic Materials ◽  
Optimum Concentration ◽  
Zirconium Titanate ◽  
Powder Synthesis ◽  
Xrd Pattern ◽  
Gel Method ◽  
Sol Gel Method

Ceramic materials based on zirconium titanate prepared by sol-gel method are used extensively in microwave, telecommunications and catalysis. In order to investigate the effects of concentration of TTIP, a series of ZrO 2– TiO 2 mixed oxides was prepared by a modified sol–gel method and varying mole fraction of TTIP from 0.002, to 0.1. The samples were characterized by XRD, TG/DTA, and SEM. The XRD pattern of 370°C calcined samples showed the formation of TiO 2 phase. The optimum concentration of TTIP in the zirconia-titania mixed oxide in the precipitation solution was 0.032 for obtaining complete coating. Each oxide was calcined between 250 and 620°C. The results showed that concentration of TTIP have a pronounced effect on particle size of the calcined zirconium titanate ( ZT ) powders. The results showed that the surface area of the composite powder increased proper to monolithic ZrO 2 powder.

Ceramic pigments on the base of the CoOZnOSiO2 system obtained by a sol-gel method

1998 ◽  
Vol 24 (4) ◽  
pp. 281-284 ◽  
Author(s):  
S. Djambazov ◽  
Y. Ivanova ◽  
A. Yoleva ◽  
N. Nedelchev
Keyword(s):  
Sol Gel ◽  
Ceramic Pigments ◽  
Gel Method ◽  
Sio2 System ◽  
Sol Gel Method

scholarly journals Application of the Sol-Gel Method at the Fabrication of PLZT:Yb3+ Ceramics

2016 ◽  
Vol 61 (3) ◽  
pp. 1441-1446 ◽  
Author(s):  
K. Osińska ◽  
M. Płońska ◽  
A. Marzec
Keyword(s):  
Thermal Evolution ◽  
Physical Adsorption ◽  
Sol Gel ◽  
Chemical Properties ◽  
Chemical Characterization ◽  
Simultaneous Thermal Analysis ◽  
Ceramic Materials ◽  
Gel Method ◽  
Sol Gel Method ◽  
Before And After

Abstract The aim of presented study was to obtain the PLZT:Yb3+ ceramics. Nanopowders of itterbium doped PLZT materials were synthesized by the sol-gel method from high quality metaloorganic precursors, as lead (II) acetate, lanthanum acetate, ytterbium acetate, zirconium (IV) propoxide and titanium (IV) propoxide. Anhydrous acetic acid and n-propyl alcohol were used as solvents, while acetyloacetone was added as stabilizer of hydrolysis reactions. Thermal evolution of the dried gels, before and after calcination, was studied by the simultaneous thermal analysis. The amorphous PLZT:Yb3+ gels were first calcined in the furnace at T = 850°C, and then mixed in the planetary ball mill. Additionally, the mean particle sizes were calculated by means of powder specific surface area measurements, based on the BET physical adsorption isotherm. Such obtained powders were subsequently pressed into pellets, and sintered by the free sintering method at temperature T = 1250°C / 6h. The morphology of fabricated PLZT:Yb3+ ceramic powders and samples was studied using Scanning Electron Microscopy. Chemical characterization of samples was carried on using the Energy-dispersive X-ray spectroscopy - EDS system. Studies provided detailed data concerning the relationships between doping and preparing conditions on the basic physical and chemical properties of obtained ceramic materials.

scholarly journals Influence of Li2Co3 and V2O5 combined additions on the sintering and dielectric properties of Ca0.5Sr0.5TiO3 ceramics prepared from powders synthesized by sol-gel method

2014 ◽  
Vol 8 (2) ◽  
pp. 101-108
Author(s):  
Nouara Lamrani ◽  
Ahcène Chaouchi ◽  
Jerôme Bernard ◽  
Brahim Itaalit ◽  
David Houivet ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Sintering Temperature ◽  
Sol Gel ◽  
Lithium Carbonate ◽  
Ceramic Materials ◽  
Type I ◽  
Titanium Butoxide ◽  
Gel Method ◽  
Sol Gel Method ◽  
Air Atmosphere

In this work, we have studied the influence of lithium carbonate (Li2CO3) associated with the vanadium oxide (V2O5) on sintering and dielectrics properties of Ca0.5Sr0.5TiO3 ceramic materials obtained from nanopowder synthesized by sol-gel method. The nanopowder was obtained by controlled mixing of titanium butoxide dissolved in butanol-2 and acetic acid with a saturated aqueous solution of calcium acetate and strontium carbonate and subsequent drying of the formed gel at 80 ?C and calcination at 1100?C. The synthesized nanopowder was mixed with different amount of additives, and then uniaxally pressed and sintered in air atmosphere at temperature determined by dilatomertic measurements. The pure Ca0.5Sr0.5TiO3 sample obtained by this process required a sintering temperature around 1500?C. The addition of Li2CO3 combined with V2O5 improved sinterability and caused a shift of dilatimeric shrinkage curve to much lower temperatures. Thus, dense ceramics (98% of theoretical density) were obtained at sintering temperature ? 1300?C. The effect of adding Li2CO3-V2O5 on the structure of ceramics and the dielectric properties is discussed and show that type I dielectric properties (linear variation of the permittivity) are conserved, but with an increase of dielectric loss.

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