• Journal of Powder Materials
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• v.14 no.3 s.62
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• pp.165-172
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• 2007

The purpose of this study was to analyze the sintering characteristics of gold and silver nanoparticles. In this study, gold and silver nanoparticles were prepared by using Inert Gas Cndensation (IGC). The sintering temperatures for gold and silver nanoparticles were $100{\sim}1000^{\circ}C\;and\'100{\sim}500^{\circ}C$, respectively. The sintering characteristics of gold and silver nanoparticles prepared by IGC were evaluated by X-ray diffraction(XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Gold and silver nanoparticles with the size of $1{\sim}100\;nm\;and\;10{\sim}100\;nm$, respectively, were obtained. The size of sintered gold and silver nanoparticles increased with an increase in the sintering temperature. XRD data showed that silver nanoparticles were similar with polycrystal single-phase.

• Journal of the Korean Ceramic Society
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• v.31 no.4
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• pp.448-456
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• 1994

The reaction-sintered alumina and zirconia-alumina ceramics were fabricated from the Al/Al2O3 or Zl/ZrO2(Ca-PSZ) powder mixtures via the attrition milling. And the effects of the milling characteristics of used raw powders on reaction sintering were investigated. After attrition milling and isopressing at 400 MPa the Al/Al2O3 specimen was oxidated at 1200℃ for 8 hours followed by sintering at 1550℃ for 3 hours. Because mixed powders of flake-type Al with coarse alumina was much more effectively comminuted than the globular-type Al with coarse alumina powders, it's sintered body of more than 97% theoretical density was achived, but low contents of Al leads to relatively higher shrinkage of about 8%. And because coarse alumina particles was much more beneficial in cutting and reducing the ductile Al particles, using the coarse alumina powder was much more effective in reaction sintering. Fused Ca-PSZ powder was reaction sintered with Al at 1550℃ for 3 hours and low shrinkage ZrO2-Al2O3 composites were fabricated. But because Al/Ca-PSZ powder mixtures were not effectively milled the reaction sintering and densification was difficult. And the Ca ion in Ca-PSZ grains diffused into alumina grains during sintering so that the unstabilization of Ca-PSZ body was occured which gave the microcracks in the specimens.

• Journal of the Korean Ceramic Society
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• v.37 no.4
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• pp.295-301
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• 2000

The effect of V2O5 addition on the low temperature sintering of Pb(Mn1/3Sb2/3)O3-PZT ceramics, which is known as a prominent material for piezoelectric transformer application was studied, and the densification behavior and piezoelectric characteristics of the samples as a function of heating rate were also examined. V2O5 led the system to liquid phase sintering by forming liquid phase during sintering, which accelerated densification through the particle rearrangement in the early stage of sintering. The liquid phase mostly existed at grain boundaries retarded the evaporation of PbO, while the densification temperature and the weight loss of V2O5-free samples were higher than those of samples with V2O5. Faster heating improved the densification of the samples regardless of V2O5 addition. The low temperature sintering at 100$0^{\circ}C$ was achieved in PMS-PZT ceramics with high density and reasonable dielectric and piezoelectric characteristics. This result revealed optimistic way to the development of multi-layered piezoelectric transformers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04a
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• pp.78-79
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• 2009

We have investigated low temperature sintering characteristics of organic Ag complex. Organic Ag complex was coated on the glass substrate by spin coating method. The coated Ag complex was sintered in an air atmosphere. The sintering temperature was varied from 30 to $80^{\circ}C$ and sintering time was varied from 1 to 228 hour. The sheet resistance was abruptly changed at $80^{\circ}C$-6h, $65^{\circ}C$-24h, $30^{\circ}C$-228 hour and the thickness of the coated film was significantly decreased. The sheet resistance of Ag films were about $0.53\;{\Omega}/{\square}$ at the $80^{\circ}C$ - 12hour.

• Korean Journal of Materials Research
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• v.15 no.3
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• pp.143-148
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• 2005

The microstructure, electrical properties, and clamping voltage characteristics of $ZnO-Pr_6O_{11}-CoO-Cr_2O_3-Y_2O_3(ZPCCY)-based$ varistor ceramics sintered at $1350^{\circ}C$ were investigated as a function of sintering time from 1 to 3 h. With increasing sintering time, the average grain size and density increased in the range of $11.4\~16.0\;{\mu}m$ and $5.34\~5.54g/cm^3$, respectively, in accordance of increasing sintering time. The nonlinear exponent decreased in the range of $60\~26$ and the leakage current increased in the range of $1.3\~10.7\;{\mu}A$ with increasing sintering time. The clamping voltage ratio increased in the range $1.58\~1.65$ for ratio surge current of 10 A as the sintering time increased.

• Journal of the Korean Ceramic Society
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• v.27 no.2
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• pp.283-287
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• 1990

The study was aimed at investigating sintering characteristics, the overall properties from the ternary Li2O-Al2O3-SiO2 system. This system, which was considered without additives and selected five compositions, was studied with variation of the amount of SiO2. The reactivity of the system was observed by D.T.A.. Characteristics of sintering, microstructure, property and stability of produced phase were studied. It was found that because the range of sintering was narrow and the temperature of sintering was close to the melting temperature, the sintering by the general method was difficult. Also, these linear thermal expansion coeffecients were measured.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.4
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• pp.215-220
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• 2000

This study on the incineration ash and sintering pellet from sewage sludge was carried out to evaluate the possibility of recycling in sewage sludge disposal. The samples used in this experiment were raw sewage sludge, its incineration ash, and sintering pellet. The characteristics of the three sample types were identified using X-ray diffraction(XRD), X-ray fluorescence(XRF), atomic absorption spectroscopy(AAS), and inductively coupled plasma spectroscopy(ICP). The chemical compositions of all three sample types were similar in their clay component, however, the sewage sludge had a high content of organic materials. From an analysis of the mineral content of the three sample types, the conversion of their compositions was found to be relative to temperature. Accordingly, incineration ash and sintering pellet both have potential for use as a functional construction material.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.431-432
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• 2008

We have investigated low temperature sintering characteristics of organic Ag complex. Organic Ag complex was coated on the glass substrate by spin coating method. The coated Ag complex was sintered in an air atmosphere. The sintering temperature was varied from 100 to $300^{\circ}C$ and sintering time was varied from 1 to 4 min. The thickness of the coated film was significantly decreased as the film was sintered at the temperature between 110 and $120^{\circ}C$. The sintered Ag film at temperature higher than $115^{\circ}C$ shows very low sheet resistance less than 1 ${\Omega}{/\square}$.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1400-1401
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• 2006

In this study, in order to develop low temperature sintering piezoelectric ceramics for multilayer piezoelectric actuator, $PbSr(Mn_{1/3}Nb_{2/3})O_3-(Mg_{1/3}Nb_{2/3})O_3-(ZrTi)O_3$ ceramics were fabricated using $Na_{2}CO_{3}-Li_{2}CO_{3}$ as sintering aids and their piezoelectric and dielectric characteristics were investigated according to the sintering tempo rature. At the sintering temperature of $900^{\circ}C$, the density, electrom echanical coupling factor(kp), mechanical quality factor(Qm) and dielectric constant(${\varepsilon}r$) of specimen showed the optimum value of $7.730[g/cm^2]$, 0.552, 1134, 1492 and 330[pC/N], respectively.

• Journal of Technologic Dentistry
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• v.39 no.3
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• pp.145-152
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• 2017

Purpose: This study sought to identify changes in the mechanical characteristics and color of zirconia according to different sintering temperatures of the substance. Methods: This study processed some specimens of zirconia into those of $8mm(H){\times}10mm(W){\times}50mm(L){\pm}0.1$ each, and sintered them at $1450{\sim}1600^{\circ}C$ on a $50^{\circ}C-interval$ basis in order to examine how their mechanical characteristics and color are changed. Each specimen sintered using the spectral colorimetric apparatus (Easyshade, VITA, Germany) was observed for each of the color change by sintering temperature. Results: When those specimens were sintered at $1450{\sim}1600^{\circ}C$, they were 0% in absorption ratio and porosity, 20% in shrinkage ratio and $6.10g/cm^3$ in specific gravity. Absorption ration, porosity, shrinkage ratio and specific gravity all didn't vary depending on the sintering temperature. The fracture strength of the specimens was highest or 1037MPa at the sintering temperature of $1550^{\circ}C$ and a little lower or 989MPa at that of $1600^{\circ}C$. No variation in L* value was found depending on the sintering temperature of the specimens, while c* value was highest at that of $1450^{\circ}C$. In addition, h* value was highest when the specimens was sintered at $1550^{\circ}C$. Conclusion: This study could determine how zirconia shows changes in mechanical characteristics and color in accordance with different temperatures of its sintering. It is necessary to supplement the physical data of colored transparent zirconia block which is expected to be widely used in clinical practice.