Preparation and Electrical-Conductive Property of SnO2-Based Ceramics

2010 ◽  
Vol 105-106 ◽  
pp. 367-370 ◽  
Author(s):  
Guo Qiang Luo ◽  
Qiang Shen ◽  
Q.Z. Li ◽  
J. Li ◽  
Dong Ming Zhang ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Electrical Resistivity ◽  
Liquid Phase ◽  
Sintering Temperature ◽  
Processing Conditions ◽  
Sintering Aid ◽  
Densification Temperature ◽  
Wide Range ◽  
Electrical Resistivities ◽  
Conductive Property

In this study, SnO2-based ceramics, with CuO as sintering aid and Sb2O3 as activator of the electrical conductivity, was obtained by pressure-less sintering at 1100°C ~ 1470°C. Addition of antimony leads to a higher densification temperature. Densification behavior and microstructure development are strongly dependant on CuO and Sb2O3. CuO gives rise to a liquid phase; Sb2O3 retards the formation of liquid phase and hinders the growth of grain. The electrical resistivities of SnO2-based ceramics vary in a wide range from 10-2 to 107 Ω•cm, depending on starting compositions and processing conditions. The electrical resistivities of samples with different amounts of CuO and Sb2O3 show different trends with the increasing of sintering temperature. The addition of antimony rapidly promotes electrical conductivity of SnO2-based ceramics containing CuO as the solid solution reaction of Sb2O3-SnO2. As the additions of CuO and Sb2O3 are the same, the electrical resistivity arrives the minimal value of 4.72×10-2 Ω•cm for 99%SnO2+0.5%CuO +0.5%Sb2O3 at 1470°C. More content of Sb2O3 than CuO causes the degression of density and the rising of electrical resistivity of ceramics.

Preparation and Electrical-Conductive Property of SnO2-Based Ceramics with 0.5% CuO and Sb2O3

2007 ◽  
Vol 352 ◽  
pp. 263-266 ◽  
Author(s):  
Lian Meng Zhang ◽  
Guo Qiang Luo ◽  
J. Li ◽  
Dong Ming Zhang ◽  
Qiang Shen
Keyword(s):  
Electrical Conductivity ◽  
Electrical Resistivity ◽  
Probe Method ◽  
Pressureless Sintering ◽  
Densification Behavior ◽  
Microstructure Development ◽  
Sintering Aid ◽  
Wide Range ◽  
Electrical Resistivities ◽  
Conductive Property

In this study, SnO2-based ceramics, with 0.5%CuO as sintering aid and Sb2O3 as activator of the electrical conductivity, was obtained by pressureless sintering at 1450°C for 5 h. Densification behavior and microstructure development strongly depend on Sb2O3. The characteristization of microstructures on Sb2O3 concentrations are analyzed by SEM. A small amount of CuO improves densification; Sb2O3 retards the densification of SnO2-based ceramic. The electrical resistivities of SnO2-based ceramics with different contents of Sb2O3 are measured by the standard four probe method and varied in a wide range. The electrical resistivity arrives the minimal value of 4.964×10-2 0·cm for 99%SnO2+0.5%CuO +0.5%Sb2O3. More content of Sb2O3 than that of CuO causes the degression of density and the increasing of electrical resistivity of ceramics.

The Influence of Bi2O3 on SiO2-Al2O3-B2O3-RO Glass Propertiesarts

2014 ◽  
Vol 887-888 ◽  
pp. 86-89
Author(s):  
Ying Liang Tian ◽  
Jing Zhang ◽  
Shi Bing Sun ◽  
Ji Ye Fan
Keyword(s):  
Electrical Resistivity ◽  
High Temperature ◽  
Expansion Coefficient ◽  
Bismuth Oxide ◽  
Sintering Temperature ◽  
Oxide Content ◽  
Basic Composition ◽  
Wide Range ◽  
Melt Annealing ◽  
Annealing Method

In the paper, regarded SiO2-Al2O3-B2O3-RO system as basic composition, high-temperature glass glaze was prepared successfully by using Bi2O3 in place of Al2O3, and traditional melt annealing method was adopted .The influence of Bi2O3 on expansion coefficient, sintering temperature, electrical resistivity was investigated by DIL-2008, SJY sintering imager, Keythley2410. The results show that the sintering temperature of glass glaze has a wide range, which can reach 270°C, so it is easy to sinter; with the increasing of bismuth oxide content, expansion coefficient of glass glaze gradually increases, whereas sintering temperature and electrical resistivity continuously decreases.

Experimental Research on the Conductive Property of MWCNT Nanopaper

2015 ◽  
Vol 727-728 ◽  
pp. 137-140
Author(s):  
A Ying Zhang
Keyword(s):  
Electrical Conductivity ◽  
Electrical Resistivity ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
The Self ◽  
Vacuum Deposition ◽  
Temperature Dependent ◽  
Polycarbonate Membrane ◽  
Multi Walled Carbon Nanotube ◽  
Conductive Property

This paper presents a systematic study of the nano-sized structure and temperature dependent electrical properties. A method of synthesizing the self-assembled multi-walled carbon nanotube (MWCNT) nanopaper on hydrophilic polycarbonate membrane was explored. The process is based on the very well-defined dispersion of nanotube and controlled pressure vacuum deposition procedure. The experiment results show that the ratio changes of MWCNT in the nanopaper could lead to the changes in the electrical conductivity efficiency of the nanopaper. Furthermore, the electrical resistivity of MWCNT nanopaper decreased as temperature increase.

Semiconducting BaTiO3 ceramic prepared by low temperature liquid phase sintering

1998 ◽  
Vol 13 (3) ◽  
pp. 660-664 ◽  
Author(s):  
I. Zajc ◽  
M. Drofenik
Keyword(s):  
Liquid Phase ◽  
Grain Boundary ◽  
Sintering Temperature ◽  
Positive Temperature Coefficient ◽  
Liquid Phase Sintering ◽  
Positive Temperature ◽  
Sintering Aid ◽  
Ptcr Effect ◽  
Temperature Coefficient Of Resistivity ◽  
Temperature Liquid

Donor-doped BaTiO3 ceramics were prepared by adding PbO B2O3 SiO2 as a sintering aid. Semiconducting BaTiO3 was obtained at a sintering temperature of 1100 °C. The sintered samples exhibit the Positive Temperature Coefficient of Resistivity (PTCR) effect, which depends on the amount of liquid phase, the concentration of the donor-dopant, and the sintering temperature. The cold resistivity of the samples decreases when the sintering temperature increases. The increase of the grain boundary resistivity and hence of the cold resistivity at lower sintering temperatures was explained by applying the diffusion grain boundary layer model.

Low-Temperature Sintering and Microwave Dielectric Properties of CaWO4-Mg2SiO4 Ceramics

2014 ◽  
Vol 933 ◽  
pp. 12-16 ◽  
Author(s):  
Chung Long Pan ◽  
Ping Cheng Chen ◽  
Tsu Chung Tan ◽  
Wei Cheng Lin ◽  
Chun Hsu Shen ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Liquid Phase ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Liquid Phase Sintering ◽  
Low Temperature Sintering ◽  
Sintering Aids ◽  
Sintering Aid ◽  
Microwave Dielectric

The effect of V2O5addition on the microstructures and the microwave dielectric properties of 0.9CaWO4-0.1Mg2SiO4(9CWMS) ceramics prepared by conventional solid-state routes have been investigated. The V2O5were selected as liquid phase sintering aids to lower the sintering temperature of 9CWMS ceramics. A small amount of V2O5(0.25~1 wt%) were used for sintering aid and led to high densification at 1050°C. The dielectric properties of 9CWMS ceramics with V2O5additions are strongly dependent on the densification, the microstructure. As the amount of V2O5additives increased from 0.25 to 1.0 wt%, the dielectric constantsεrdecreased following the trend with density. The quality valuesQdecreased with the increase of V2O5amount for all sintering temperatures. The 0.25 wt% V2O5-doped 0.9CaWO4-0.1Mg2SiO4ceramicssintered at 1080°C for 2 h had the optimum dielectric properties: εr= 5.7;Q×f= 73000 (at 14 GHz).

Electrical Conductivity and Thermogravimetric Studies of the High-7c Superconductor YBa2Cu3Ox

1987 ◽  
Vol 99 ◽  
Author(s):  
Y. H. Han ◽  
D. W. Monroe
Keyword(s):  
Electrical Conductivity ◽  
Electrical Resistivity ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Oxygen Stoichiometry ◽  
Linear Temperature Dependence ◽  
Linear Temperature ◽  
Electrical Conductivities ◽  
Electrical Resistivities ◽  
Electron Holes

ABSTRACTNonstoichiometry in YBa2Cu3Ox has been studied by means of equilibrium electrical conductivity and thermogravimetric method. We have observed a strong correlation between electrical resistivity and oxygen stoichiometry (x) at high temperature. Electrical resistivities increase linearly from the superconducting onset tcmperature(100 K) to 450 C where oxygen starts to evolve from this material, and then begin to deviate from linear temperature dependence. The experimental results indicate that electrical resistivity in this material is associated with the defect species (charge carrier) population due to oxygen stoichiometry. Electrical conductivities were also measured as a function of oxygen partial pressure (1 to 10−4 atm) at various temperatures. At P(OI) > 101 atm the conductivity shows a l/4th slope dependence on oxygen partial pressure while at P(0;) < 10 f atm the conductivity is proportional to P(O2)1/2- The conductivity behavior with oxygen stoichiometry suggests that the electron holes associated with Cu+ play an important role as charge carriers in this material, and even at x < 6.5 p-typc conduction is predominant.

scholarly journals Sintering Behaviors, Microstructure, and Microwave Dielectric Properties of CaTiO3–LaAlO3 Ceramics Using CuO/B2O3 Additions

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4187 ◽  
Author(s):  
Min-Hang Weng ◽  
Chihng-Tsung Liauh ◽  
Shueei-Muh Lin ◽  
Hung-Hsiang Wang ◽  
Ru-Yuan Yang
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Liquid Phase ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Liquid Phase Sintering ◽  
Sintering Aids ◽  
Sintering Aid ◽  
Microwave Dielectric ◽  
Quality Factor Q

The effect of CuO/B2O3 additions on the sintering behaviors, microstructures, and microwave dielectric properties of 0.95LaAlO3–0.05CaTiO3 ceramics is investigated. It is found that the sintering temperatures are lowered efficiently from 1600 °C to 1350 °C, as 1 wt % CuO, 1 wt % B2O3, and 0.5 wt % CuO +0.5 wt % B2O3 are used as the sintering aids due to the appearance of the liquid phase sintering. The microwave dielectric properties of 0.95LaAlO3–0.05CaTiO3 ceramics with the sintering aid additions are strongly related to the densification and the microstructure of the sintered ceramics. At the sintering temperature of 1300 °C, the 0.95LaAlO3–0.05CaTiO3 ceramic with 0.5 wt % CuO + 0.5 wt % B2O3 addition shows the best dielectric properties, including a dielectric constant (εr) of 21, approximate quality factor (Q × f) of 22,500 GHz, and a temperature coefficient of the resonant frequency (τf) of −3 ppm/°C.

THERMAL AND ELECTRICAL CONDUCTIVITY OF RHODIUM, IRIDIUM, AND PLATINUM

1957 ◽  
Vol 35 (3) ◽  
pp. 248-257 ◽  
Author(s):  
G. K. White ◽  
S. B. Woods
Keyword(s):  
Electrical Conductivity ◽  
Electrical Resistivity ◽  
High Purity ◽  
Low Temperatures ◽  
Rapid Rate ◽  
Transition Elements ◽  
Electron Collisions ◽  
Electrical Conductivities ◽  
Electrical Resistivities ◽  
The Ideal

Measurements are reported of the thermal and electrical conductivities of the transition elements Rh, Ir, Pt in a state of high purity; the rapid rate of decrease of the "ideal" thermal and electrical resistivities with temperature, particularly in Rh and Ir, suggests that s–d transitions are not a dominant resistive mechanism at low temperatures in these metals, in contrast to palladium, iron, and nickel, which were studied previously. The electrical resistivity of platinum is in general agreement with the earlier results of de Haas and de Boer (1934); the quadratic dependence on temperature observed below about 10° K. suggests that electron–electron collisions may well be an important factor in this metal.

A study of the palladium‒platinum‒hydrogen system over a wide range of hydrogen pressures

1983 ◽  
Vol 386 (1791) ◽  
pp. 309-332 ◽  
Keyword(s):  
Solid Solution ◽  
Electrical Resistivity ◽  
Hydrogen Pressure ◽  
Hydrogen Gas ◽  
Β Phase ◽  
Electrode Potentials ◽  
Wide Range ◽  
Electrical Resistivities ◽  
Hydrogen Systems ◽  
Palladium Platinum

Measurements with an extensive series of palladium‒platinum alloys, of changes in electrical resistivity due to direct absorption of hydrogen from hydrogen gas at pressures up to 30 kbar (3 GPa) have been made at 25 and 75°C. Interrelations at 25°C between hydrogen content, electrical resistivity and hydrogen pressures of up to ca . 20 bar have also been derived, for the more palladium-rich alloys, from measurements of electrode potentials. Substantial changes of electrical resistivity, indicative of significant hydrogen absorption, have been found to occur over increasingly higher ranges of pressures with increasing platinum contents. However, the overall form of relations between electrical resistivity and equilibrium hydrogen pressure (or fugacity) remains essentially the same, showing a gradually accelerating increase of resistivity with increasing hydrogen pressure up to maximum values (corresponding to relative electrical resistivities R/R 0 of ca . 1.5‒2) followed by a decrease back to close to initial hydrogen-free values. Possibilities are discussed of the association of ranges of the most marked changes of resistivity with regions of α and β phase hydride coexistence or with ‘supercritical’ regions of continuous hydrogen solid solution. An extrapolation of a trend of experimental results suggests that it may be possible to attain a solid solution of hydrogen in pure platinum up to a composition of ca . PtH 0.25 at hydrogen pressures of ca . 100 kbar at 25°C. Other factors discussed are: alterations of thermodynamic parameters with increasing platinum content, and decreasing hysteretic differences between relations derived during increases and decreases of hydrogen pressure. Particular comparisons are made with behaviour in the palladium‒rhodium‒hydrogen and palladium‒nickel‒hydrogen systems.

Preparation and Dielectric Properties of Li2O Doped BaZr0.25Ti0.75O3 Ceramics

2011 ◽  
Vol 284-286 ◽  
pp. 1460-1465
Author(s):  
Di Chen ◽  
Xiang Yun Deng ◽  
Jian Bao Li ◽  
Li Ming Wang ◽  
Xin Zheng Wu ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Liquid Phase ◽  
Sintering Temperature ◽  
Liquid Phase Sintering ◽  
X Ray Diffraction ◽  
Sintering Aid ◽  
X Ray ◽  
Ceramic Process ◽  
Low Sintering Temperature

BaZr0.25Ti0.75O3(BZT) ceramics were prepared by conventional ceramic process at a relatively low sintering temperature and with an addition of Li2O as the liquid-phase sintering aid. X-ray diffraction characterized results showed that the main crystal phase of the samples with 1.0wt% Li2O additive sintered at 1050°C～1250°C for 4h presented perovskite structure. The dielectric properties of BZT ceramics have been investigated. The dielectric constant of 1.0wt% Li2O doped BZT sintered at 1150°C decreased, and the dielectric loss increased by 0.0012 compared with that of the pure BZT sintered at 1450°C.

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