• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 추계학술발표강연 및 논문개요집
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• pp.53-53
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• 1998

• 한국세라믹학회지
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• 제45권8호
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• pp.464-471
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• 2008

The electrolyte separator for thermal battery should be easily handled and loaded a large amount of the molten salt. Ceramic fibers, especially fibrous commercial glass filters were used as an electrolyte separator and the lithium based molten salts were infiltrated into the ceramic filters. The pore structures of the ceramic filter and the melting properties of the lithium salts affected to the electrolyte loading and leakage. During the infiltration, ions of $Li^+$ and $F^-$ in the molten salts were reacted with the glass fiber and caused to be weaken the fiber strength.

• 한국세라믹학회지
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• 제23권4호
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• pp.27-34
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• 1986

In the present study an attempt was made to synthesize $10TiO_2$.$90SiO_2$ glass by Sol-Gel process. Tetra-ethyl-ortho-silane and titanium-iso-propoxide were used as precursors. As the mutual solvent ethanol and iso-propanol were used. TEOS was partially hydrolyzed with one-fold mole of $H_2O$ prior to the reaction with titanium-iso-propoxide to control the difference of hydrolysis rate of the two metal alkoxides. At gelling temperature higher than 6$0^{\circ}C$ it was difficult to obtain monolithic gels. At such a low temperature as 85$0^{\circ}C$ clear amorphous gel derived glass with Si-O-Ti bonding was obtained.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.304-304
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• 2007

고주파 모률에서 사용되는 기판소재는 저유전율과 낮은 loss 특성을 요구함으로 지속적인 연구를 필요로 한다. 지금까지의 ceramic/glass composite 에서 주로 사용된 ceramic filler는 Al2O3로 낮은 유전률을 구현에 한계가 있었다. Cordierite는 낮은 유전율 (${\varepsilon}_r$ < 4)을 나타내는 filler로서 그 가능성이 높지만 아직까지 보고된 결과들이 미흡한 실정이다. 따라서 본 연구에서는 cordierite filler와 SiO2-B2O3-Al2O3-RO (R : Zn, Sr, Ba, Ca)계의 glass를 혼합하여 LTCC용 기판소재로서의 가능성을 확인하고자 저온 동시소성이 가능한 소결온도인 $850^{\circ}C{\sim}1.000^{\circ}C$ 사이에서 소재의 소결실험을 진행하였다. 소결온도에 따른 상변화, 유전특성을 확인한 결과 filler로 사용된 cordierite상만이 관찰 되었으며 소결조건에 따라 5.0~5.5의 낮은 유전율과 1.000~1,500의 Q를 나타내는 것을 확인 하였다.

• 한국결정성장학회지
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• 제25권3호
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• pp.105-110
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• 2015

근관 치료를 위해 사용되는 섬유 강화형 포스트를 광중합 레진과 유리섬유를 이용하여 제조하였다. 제조된 포스트는 유리 섬유의 밀도가 높아짐에 따라 기계적 특성이 향상됨을 확인 할 수 있었고 광중합 레진의 점도 조절 및 진공함침 공정을 통해 미세 기공을 효과적으로 제거 할 수 있었다. 유리섬유와 광중합 레진과의 계면 결합력을 향상시키기 위해 유리 섬유 표면을 실란 커플링제를 사용하여 표면처리를 하였으며, 유리섬유의 표면처리는 유리 섬유 표면에 레진의 젖음성을 향상시켜 레진과의 결합 특성을 향상시키고 포스트의 기계적 특성을 향상시킴을 확인할 수 있었다.

• The Journal of Advanced Prosthodontics
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• 제6권3호
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• pp.151-156
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• 2014

PURPOSE. To investigate the microtensile bond strength between two all-ceramic systems; lithium disilicate glass ceramic and zirconia core ceramics bonded with their corresponding glass veneers. MATERIALS AND METHODS. Blocks of core ceramics (IPS e.max$^{(R)}$ Press and Lava$^{TM}$ Frame) were fabricated and veneered with their corresponding glass veneers. The bilayered blocks were cut into microbars; 8 mm in length and $1mm^2$ in cross-sectional area (n = 30/group). Additionally, monolithic microbars of these two veneers (IPS e.max$^{(R)}$ Ceram and LavaTM Ceram; n = 30/group) were also prepared. The obtained microbars were tested in tension until fracture, and the fracture surfaces of the microbars were examined with fluorescent black light and scanning electron microscope (SEM) to identify the mode of failure. One-way ANOVA and the Dunnett's T3 test were performed to determine significant differences of the mean microtensile bond strength at a significance level of 0.05. RESULTS. The mean microtensile bond strength of IPS e.max$^{(R)}$ Press/IPS e.max$^{(R)}$ Ceram ($43.40{\pm}5.51$ MPa) was significantly greater than that of Lava$^{TM}$ Frame/Lava$^{TM}$ Ceram ($31.71{\pm}7.03$ MPa)(P<.001). Fluorescent black light and SEM analysis showed that most of the tested microbars failed cohesively in the veneer layer. Furthermore, the bond strength of Lava$^{TM}$ Frame/Lava$^{TM}$ Ceram was comparable to the tensile strength of monolithic glass veneer of Lava$^{TM}$ Ceram, while the bond strength of bilayered IPS e.max$^{(R)}$ Press/IPS e.max$^{(R)}$ Ceram was significantly greater than tensile strength of monolithic IPS e.max$^{(R)}$ Ceram. CONCLUSION. Because fracture site occurred mostly in the glass veneer and most failures were away from the interfacial zone, microtensile bond test may not be a suitable test for bonding integrity. Fracture mechanics approach such as fracture toughness of the interface may be more appropriate to represent the bonding quality between two materials.

• 한국재료학회지
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• 제29권10호
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• pp.639-646
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• 2019

Ink-jet printing is a manufacturing process technology that directly prints a digitalized design pattern onto a substrate using a fine ink jetting system. In this study, environmentally friendly yellow aqueous ceramic ink is synthesized by mixture of distilled water, yellow ceramic pigment and additives for ink-jet printing. The graft polymer, which combines electrostatic repulsion and steric hindrance mechanism, is used as a surfactant for dispersion stability of aqueous ceramic ink. Synthesized ceramic ink with graft polymer surfactant shows better dispersion stability than did ceramic ink with PAA surfactant; synthesized ink also shows desirable ink-jet printability with the formation of a single ink droplet during printability test. Finally, ceramic ink printed on glass substrate and ceramic ink with graft polymer surfactant shows a high contact angle without surface treatment on glass substrate. Consequently, it is confirmed that the ceramic ink with graft polymer surfactant can achieve high printing resolution without additional surface treatment process.

• 한국세라믹학회지
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• 제31권8호
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• pp.902-910
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• 1994

Residual stress measurements were made for cylindrical glass rods to compare experimental results with the calculated values obtained by Instant Freezing Model. According to the photoelastic measurements, the stress ratio of surface compression and center tension was increased from 1.4 to 2.0 as the heat-treatment temperature was lowered, the fictitious forzen temperature was found to be closer to the heat-treatment temperature and the fictitious coefficient was increased.

• 한국세라믹학회지
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• 제14권4호
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• pp.248-255
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• 1977

The effect of firing temperature, soaking time and batch composition upon the glass phase and pore formation as well as their distribution in slag foamed glass was investigated. Sulfur dioxide gas produced by the oxidation and reduction of metal sulfide in waterslag was attributed to foam forming agent. Slag foamed glass matrix was mainly composed of 35~60% glas phase and melilite crystalline phase. The increment of bentonite addition in batch lowered the foam forming temperature in studied system. The result showed also that the foam size distribution was broadened as th firing temperature wa inbereased.

• 마이크로전자및패키징학회지
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• 제5권2호
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• pp.53-58
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• 1998

Sintering and dielectric characteristics of substrates were estimated by mixing rate of alumina and potashborosilicate glass(PBSG) powders. PBSG powders were used 7761(corning code)and alumina powders were used in extra pure rate(99.9%) and had 0.1 ${\mu}$m mean size. After ball milling with organic additives green sheets which were casted by doctor blade machine were sintered at 800$^{\circ}C$ for 1∼3hrs. Microstructure, linear shrinkage and dielectric constant of substrates were surveyed in order to fabricate low-dielectric and low tem-perature sintering substrate.