Investigation of second phase concentration effects on tribological and electrical properties of Cu-WS2 composites

AbstractPb(ZrxTi1−x)O3 (PZT) films were grown by molecular beam epitaxy using hydrogen peroxide as a source of reactive oxygen. Phase composition as well as structural and electrical properties of the films were studied by x-ray diffractometry, scanning and transmission electron microscopy, conductive atomic force microscopy, and electrical (I-V and polarization-field) measurements. The hydrogen peroxide pressure was found to control the phase composition of the films. Excess peroxide leads to PbO inclusions in PZT layers, whereas deficiency results in the TiO2 or the ZrO2 phase. The second-phase inclusions can be responsible for high leakage current in the films. Precise control over the peroxide pressure is imperative for single-phase PZT films with good ferroelectric properties.

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Composition Materials With Metal Matrix Condensed from the Vapor Phase

Journal of Material Science and Technology Research ◽

10.31875/2410-4701.2021.08.4 ◽

2021 ◽

Vol 8 ◽

pp. 24-29

Author(s):

N.I. Grechanyuk ◽

V.G. Grechanyuk ◽

A.F. Manulyk

Keyword(s):

Porous Materials ◽

Vapor Phase ◽

Metal Matrix ◽

Open Porosity ◽

Deposition Temperature ◽

Second Phase ◽

Pore Sizes ◽

Phase Concentration ◽

Composition Materials ◽

Condensed Materials

In this article, the present-day problems of microporous condensed materials obtained from the vapor phase are discussed. The pore sizes are regulated by the amount of the second phase concentration and the deposition temperature. The oxides, fluorides, and sulfides can be used as the second phase and non-removable inclusions. The open porosity can be regulated from 0% to 50 %of the porosity and with average porose sizes of 0.1 to 8 µm. The condensed micro-porous materials can be deposited in coating form or the form of massive bulk sheet materials with a thickness of up to 6 mm and a diameter of 1m.

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Structure and properties of K0.5Na0.5Nb0.96Sb0.04O3 piezoelectric ceramics doped by CuO

Functional Materials Letters ◽

10.1142/s1793604721510425 ◽

2021 ◽

pp. 2151042

Author(s):

Qiyi Yin ◽

Yu Wang ◽

Quanzheng Zhang ◽

Kunhong Hu ◽

Jie Yang ◽

...

Keyword(s):

Electrical Properties ◽

Low Voltage ◽

Piezoelectric Ceramics ◽

Second Phase ◽

Test Results ◽

Moderate Amount ◽

Test Analysis ◽

Sintering Additives ◽

Sintering Properties ◽

Piezoelectric Devices

Envisaged through adding sintering additives to achieve low-temperature sintering preparation, in order to overcome the volatilization of sodium ions and potassium ions in the high-temperature preparation, so as to improve the density and electrical properties of KNN-based piezoelectric ceramics. This research uses traditional solid-state sintering technology, a high density, high properties lead-free piezoelectric ceramics, KNNSC-[Formula: see text], successfully prepared with sintering additives CuO. The modern test analysis of XRD and SEM shows that a moderate amount of CuO doped in the range of research can form a single perovskite structure of an orthorhombic structure, not found in any second phase, and can promote grain evenly growing and improve the sintering properties of KNN-based piezoelectric ceramics. The KNNSC-0.04 ceramics exhibit excellent electrical properties through various electrical tests such as [Formula: see text] = 238pC/N, [Formula: see text]= 47%, [Formula: see text]= 1049, tan[Formula: see text]= 2.4%, [Formula: see text] = 25.6 [Formula: see text]C/cm2, [Formula: see text] = 1.24 kV/mm, respectively. These test results show that the KNNSC-[Formula: see text] piezoelectric ceramics have great potential to be applied in middle- and low-voltage piezoelectric devices.

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Electrical Properties of Modified BNT Based Lead-Free Ceramics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.872.87 ◽

2016 ◽

Vol 872 ◽

pp. 87-91

Author(s):

Supalak Manotham ◽

Tawee Tunkasiri ◽

Pharatree Jaita ◽

Pichitchai Butnoi ◽

Denis Russell Sweatman ◽

...

Keyword(s):

Dielectric Constant ◽

Solid State ◽

Electrical Properties ◽

Sintering Temperature ◽

Ferroelectric Properties ◽

Lead Free ◽

Second Phase ◽

X Ray Diffraction ◽

X Ray ◽

Lead Free Ceramics

The properties of modified Bi0.5Na0.5TiO3 (BNT) based lead-free ceramics were investigated. The BNT-based ceramics were prepared by a solid-state mixed oxide method Phase formation was determined by X-ray diffraction technique (XRD). The X-ray diffraction analysis of the ceramics suggested that all samples exhibited a perovskite structure without second phase. The value of dielectric constant increased with increasing in sintering temperature. Moreover, high sintering temperatures could improve ferroelectric properties of BNT base lead-free ceramics.

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Effect of La Dopant on Electrical Properties of Pb(Zr,Ti)O3 Thin Film Capacitors

MRS Proceedings ◽

10.1557/proc-596-211 ◽

1999 ◽

Vol 596 ◽

Cited By ~ 1

Author(s):

Chang Jung Kim ◽

Ilsub Chung

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrical Properties ◽

Lead Zirconate Titanate ◽

Random Access ◽

Lead Zirconate ◽

Second Phase ◽

Pzt Thin Films ◽

Si Substrates ◽

Thin Film Capacitors

AbstractLanthanum doped lead zirconate titanate (PZT) thin films have been prepared on Pt/IrO2/Ir/SiO2/Si substrates to improve the ferroelectric and retention properties. The microstructure and electrical properties of the PZT capacitors were evaluated as a function of La content. The crystalline orientation was appreciably influenced by the addition of La in PZT thin films. The microstructures of films containing 0 and 0.5 mol% La were single phase perovskite, but for La = 1 mol%, a second phase was detected by SEM observation. The 0.5 mol% La doped PZT thin film capacitor showed the best ferroelectric and retention properties for ferroelectric random access memory compared to non-doped PZT.

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Effects of lithium oxide on the electrical properties of CuO at low temperatures

Journal of Materials Research ◽

10.1557/jmr.1990.1739 ◽

1990 ◽

Vol 5 (8) ◽

pp. 1739-1744 ◽

Cited By ~ 54

Author(s):

F. Lanza ◽

R. Feduzi ◽

J. Fuger

Keyword(s):

Electrical Properties ◽

Single Phase ◽

Lithium Oxide ◽

Antiferromagnetic Order ◽

Second Phase ◽

Strong Decrease ◽

X Ray ◽

Resistivity Measurements ◽

Calorimetric Measurements ◽

Straight Lines

We present an investigation of the influence of four dopant lithium concentrations on the electrical properties of CuO. X-ray measurements have revealed a single phase formed up to 4.2 at. % of Li, and a second phase formed, Li2CuO2, in the case of 10.5 at. % of Li concentration. The log(ρ/T) vs 1/T data are better represented by two straight lines than by one and show an initial strong decrease of the conduction activation energies for small contents of Li (<1.7 at. %), which becomes weak for larger contents. The change in slope observed in the resistivity measurements as a function of temperature has also been investigated by calorimetric measurements, revealing a specific heat anomaly which can be associated with the antiferromagnetic order transition.

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Effect of Sm2O3 on the Electrical Properties of TiO2-Ta2O5-Based Capacitor-Varistor Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.213.246 ◽

2011 ◽

Vol 213 ◽

pp. 246-249

Author(s):

Tian Guo Wang ◽

Qun Qin ◽

Dong Jian Zhou

Keyword(s):

Rare Earth ◽

Dielectric Properties ◽

Electrical Properties ◽

Rare Earth Oxide ◽

Dielectric Constants ◽

Second Phase ◽

Electrical Behavior ◽

Effective Boundary ◽

Electrical Permittivity ◽

Change Of Microstructure

TiO2 ceramics doped with 0.1 mol% Ta2O5 and different concentrations of rare earth oxide Sm2O3 were obtained by sintering at 1450 °C. As a varisor material, the microstructure, the nonlinear electrical behavior and dielectric properties of these ceramics were investigated. SEM and XRD were carried out to study the change of microstructure. The results show that there exist second phase (Sm2Ti2O3) on the surface on the surface of TiO2 grains. The ceramics have nonlinear coefficients of α = 2.0-4.0 and ultrahigh relative dielectric constants which is up to 104. The sample doped with 0.5 mol% Sm2O3 exhibits high nonlinear constant of 3.7, low breakdown voltage of 21.5 v/mm, ultrahigh electrical permittivity of 4.25× 104 and low tanδ of 0.37. It is suggested that the sample doped with 0.5 mol% Sm2O3 forms the most effective boundary barrier layer. The defects theory was introduced to illustrate the nonlinear electrical behavior of TiO2-Ta2O5-Sm2O3 varistor ceramics.

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Effects of Second Phase and Defect on Electrical Properties in Bi0.5Na0.5-xKxTiO3 Lead-Free Piezoelectric Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.1343 ◽

2011 ◽

Vol 284-286 ◽

pp. 1343-1348

Author(s):

Pin Yi Chen ◽

Cheng Sao Chen ◽

Chen Chia Chou ◽

Tseung Yuen Tseng ◽

Haydn Chen

Keyword(s):

Electrical Properties ◽

Oxygen Vacancies ◽

Defect Formation ◽

Secondary Phase ◽

Second Phase ◽

Valence Transition ◽

X Ray ◽

Potassium Titanate ◽

A Site ◽

Li Substitution

Second phase and defect formation mechanism of (Bi0.5(Na1-xKx)0.5)TiO3 (BNKT100x) ceramics were investigated using electron microscopy, x-ray photoelectron spectroscope (XPS) and electrical properties measurements. Experimental results indicated that second phase formation induces Bi-rich regions and compositional inhomogeneity within matrix due to thermodynamic stability of potassium titanate. Ti valence transition for BNKT ceramics sintered in air might be ascribed to formation of the secondary phase, rather than simply attributed to volatilization of bismuth. Li substitution at A-site in BNKT ceramics suppresses formation of the second phase and Ti valence transition. Appropriate Li doped BNKT ceramics suppress oxygen vacancies and titanium valence transition, and therefore decrease the leakage current.

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