• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.303-304
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• 2005

Add $Li_2CO_3$ to $(Ba_{0.6}Sr_{0.4})$ $TiO_3$ powder to lower sitering temperature in this research, made thick film by tape casting method. Investigated about sitering temperature and physical properties that added $Li_2CO_3$ Even if lower sitering temperature about $200^{\circ}C$ adding $Li_2CO_3$ 10wt.%, density was near to 5.7$g/cm^3$ that is theoretical values, and crystal structure examined as perobeuseukaiteu senior after sintering.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.656-658
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• 2004

Pb$(Zr_{0.8}Ti_{0.2})TiO_3$ powder were prepared by the sol-gel method using a solution of Pb-acetate, Zr n-propoxide and Ti iso-propoxide. PZT thick film were fabricated by the screen printing method, and the structural and ferroelectric properties asafunting of the sintering temperature were studied. PZT film thickness, obtained by four screen printing, was approximately $70\sim90{\mu}m$. The relative dielectric constant and the dielectric loss of the PZT thick film sintered at $1050^{\circ}C$t were approximately 676 and 1.4%, respectively. The remanent polarization and the coercive field of the PZT thick film sintered at $1050^{\circ}C$ were $21.15{\mu}C/cm^2$ and 10.1 kV/cm, mapetively

• Korean Journal of Metals and Materials
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• v.49 no.5
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• pp.367-373
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• 2011

This paper studies the experimental method that uses the homogeneous precipitation method to prepare mica flakes coated with anatase-type titania pearlescent pigment with urea as precipitant. The optimum technology parameters, the chemical composition, the microstructure, and the color property of resulting pigments are discussed. The coating principle of mica coated titania with various coating thickness is analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy(TEM) and tested by spectrophotometer analysis. The colored nanocrystalline pigments with different morphology and coating thickness 45-170 nm were prepared by homogeneous precipitation treatment of $TiOSO_4$(titanum oxysulfate) aqueous solutions. Characterizations on the pigments show that the pearlescent effects of the pigments depend mainly on mica size, thickness of the metal oxide deposit, its chemical composition, and crystal structure.

• Journal of Ceramic Processing Research
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• v.20 no.spc1
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• pp.86-91
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• 2019

A solid-state route was used to prepare sodium titanium oxide (NTO, Na2Ti3O7) as a solar heat protecting material with an impressive solar reflectance (TSR = 94.3%) using a high refractive index rutile TiO2. The solar reflectance of the synthesized NTO was measured using UV-Vis-NIR spectrophotometer. Solar reflectance property of the synthesized compound depends on the calcination temperature. The solar reflectance property of the synthesized NTO powder was compared with commercial rutile TiO2. The compound synthesized at 900 ℃ for 24 hrs had remarkable solar reflectance 94.3% than that calcined below 900 ℃. Crystalline nature, structural property, morphology and optical properties of NTO powders were characterized and analyzed using XRD, FE-SEM, EDS and UV-Vis-NIR spectrophotometer. From the results, we guessed that NTO would be a suitable "solar heat protecting candidate" for energy-saving applications in coating industries.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1800-1802
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• 1999

Electroluminescence is occurred when phosphor is located in electric field. In this paper, we made powder electroluminescent device (PELD) with structured ITO film/phosphor/Insulator/silver paste. The transparent electrode was ITO film and green(2704-01) and orange(2702-02) and blue-green(2703-01) were used as phosphor. The insulator was $BaTiO_3$ and $Y_2O_3$, back electrode was silver paste. To investigate electrical and optical properties of PELDs, EL spectrum, Brightness, Transferred charge density using Sawyer-Towers circuit was measured.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1526-1528
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• 1999

In this papaer, 7-segment was implemented using AC powder EL. ZnS:Cu and $BaTiO_3$ was used as a phosphor and dielectric respectively. The preparation of phosphor and dielectic layer was performed with screen printing. The implemented system of 7-segment was divided as following; EL display. driving circuit. software for driving. The properties of fabricated devices was measured with EL spectrum. brightness and J-V.

• Journal of Ocean Engineering and Technology
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• v.15 no.3
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• pp.69-74
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• 2001

This paper was to investigate of a adhesiveness for the plasma sprayed coating materials did salt spray by acoustic emission method in tensile loadings. The powders used for the coating were nickel aluminum composite powder Ni-4.5wt.%Al and titanium dioxide powder $TiO_2$. These powders were coated on a carbon steel S45C by plasma spray method. The result solution was a 5% NaCl and the slat spray times were 2, 5 and 10 hours respectively. The salt solution penetrated into the surface of the substrate through pore of the coating layer built in the process of plasma spay. Corrosion productions formed on the surface of substrate. The adhesiveness between the substrate and the coating layer is weaken by corrosion and the exfoliation initiated chiefly at the corrosion surface of the substrate. The AE events and energy of the corroded coating specimens decreased as the salt spray times increased.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.1
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• pp.51-53
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• 2008

A new nano-particle deposition system (NPDS) was developed for a ceramic and metal coating process. Nano- and micro-sized powders were sprayed through a supersonic nozzle at room temperature and low vacuum conditions to create ceramic and metal thin films on metal and polymer substrates without thermal damage. Ceramic titanium dioxide ($TiO_2$) powder was deposited on polyethylene terephthalate substrates and metal tin (Sn) powder was deposited on SUS substrates. Deposition images were obtained and the resulting chemical composition was measured using X-ray photoelectron spectroscopy. The test results demonstrated that the new NPDS provides a noble coating method for ceramic and metal materials.

• Journal of Powder Materials
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• v.1 no.1
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• pp.21-26
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• 1994

Aluminum was deposited on aluminum oxide powders using a fluidized bed reactor at atmospheric pressure. The aluminum oxide powders were irregular flakes with acute angles and the average particle size was 26 $\mu\textrm{m}$. The fluidized bed was formed by flowing argon gas at the velocity of 60 cm/sec. The optimal fluidization condition was obtained with the reactor designed to be tapered so that the fluid velocity decreases as the fluidizing gas goes up along the reactor. Aluminum was deposited by flowing TiBA(Triisobutylaluminum) evaporated at$250^{\circ}C$ through the fluidized bed reactor heated to 350~$450^{\circ}C$. The result from the analysis by XRD and EDAX confirmed the coating of aluminum and an SEM micrograph showed the conformality.

• Journal of Powder Materials
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• v.13 no.6 s.59
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• pp.445-449
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• 2006

The experimental data from the central composite design runs were utilized for mathematical models far the drilling characteristics containing linear, quadratic and interactive effects of the parameters such as volume fraction of TiC in the composites, drill speed, feed rate and drill diameter. The models were developed via stepwise selection where the insignificant effects were removed using t-test. The models were subjected to optimization of maximizing drill life and satisfying the other constraints.