• 한국세라믹학회지
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• 제44권1호
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• pp.65-69
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• 2007

For self-developed alkali-alkaline earth-silicate and commercial glass melts for plasma display panel substrate, the corrosion behavior of fused casting refractory consisting of $Al_2O_3-ZrO_2-SiO_2$ was examined at the temperature corresponding to $10^2\;dPa{\cdot}s$ of melt viscosity by static finger methode. The corroded refractory specimens showed a typical concave shape due to interfacial convection of melts at their flux line. However, the corrosion thickness by commercial glass melts was $6\sim10$ times comparing to that by the self?developed melts. From the view point of the glass composition and the role of alkaline earth in glass network, it was discussed the effect of alkali/alkaline earth diffusion and temperature on the refractory corrosion.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1985년도 추계학술대회 논문집
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• pp.21-23
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• 1985

By adding La$_2$O$_3$ to optical multicomponent glass composition, after making mother glass and core fiber that enable to enlarge the infrared transmittance region, then surveyed the optical properties. Through thermal analysis of the glass abstained by melt-quenching after selecting stable basic composition on devitrification and replace SiO$_2$ by 4-12wt% La$_2$O$_3$. As La$_2$O$_3$ increases up to l2wt% transition temperature, refractive index, density, deformation temperature increased, whereas thermal expansion coefficient decreased. As a result of inspectig transmittance in UV/VIS/IR region, visable region indicated the decrease of transmittance by increasing the La$_2$O$_3$ and transmittance region was enlarged by increasing the La$_2$O$_3$ in IR region. Also, fabricate core fiber at 820$^{\circ}C$ and severy the optical loss we could fact that La$_2$O$_3$ composition added 12wt% showed the minimum optical loss.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1181-1182
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• 2006

Y-type barium ferrite $(Ba_2Zn_2Fe_{12}O_{22})$ was prepared by the glass-ceramic method. Glasses with composition of $0.1ZnO{\cdot}0.9(0.3Fe_2O_3{\cdot}0.5BaO{\cdot}0.2B_2O_3)$ were prepared, and the precipitation behavior of Y-type ferrite from the glass matrix was investigated by heating glass specimens at various temperature. $\alpha-BaFe_2O_4$ which is a precursor of M-type ferrite $(BaFe_{12}O_{19})$ was precipitated at about 813 K and an unknown compound, phase X, was precipitated at about 850 K. M-type ferrite and Y-type ferrite started to form at about 923 K and 1103 K, respectively. The formation of Y-type ferrite was int erpreted as the result of the reaction of M-type ferrite with a melt of phase X.

• 한국전기전자재료학회논문지
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• 제30권4호
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• pp.204-209
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• 2017

Thermal and structural stability in the glass transition region of chalcogenide glasses has been investigated in terms of thermodynamics for application to various optoelectronic devices. In this study, the compositions of $Ge_xSb_{20}Se_{80-x}$ (x = 10, 15, 20, 25, and 30) were selected to investigate the glass stability according to germanium ratios. The chalcogenide bulks were fabricated by using a traditional melt-quenching method. Thin films were deposited by a thermal evaporation system, maintaining the deposition ratio of $3{\sim}5{\AA}$ in order to have uniformity. The thermal and structural properties were measured by a differential scanning calorimeter (DSC) and X-ray diffraction (XRD). The DSC analysis provided thermal parameters and theoretical glass region stabilities. The XRD analysis supported the theoretical stabilities because of where the crystallization peak data occurred.

• Macromolecular Research
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• 제14권3호
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• pp.261-266
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• 2006

Blends of silicone rubber (VMQ) and liquid crystalline polymer (LCP) were prepared using a melt blending technique in the presence and absence of glass fiber and coupling agents. The effect of glass fiber and coupling agents on the thermal, dynamic mechanical, morphological pro-perties and cure characteristics of VMQ/LCP blends were studied. The vinyl silane coupling agent showed a significant effect on the above mentioned properties of VMQ/LCP blends by reacting at the interface between VMQ and LCP. The viscosity of the VMQ/LCP blends decreased with the addition of a coupling agent. A substantial improvement in storage modulus of VMQ/LCP blends was observed in the presence of glass fiber and coupling agents. However, as a coupling agent vinyl silane proved to be better than amine for the VMQ/LCP-glass-containing blends. The thermal stability of the pure silicone rubber was higher than those of the blends. This high thermal stability of silicone rubber was attributed to the Si-O-Si bonds. However, the thermal stability of the blends decreased further in the presence of a coupling agent, possibly due to a decrease in blend crystallinity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.842-844
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• 2004

Ternary tellurite glassy systems $(CuO-V_2O_5-TeO_2)$ have been synthesised using tellurium oxide as a network former and copper oxide as network modifier. The addition of a transition-matal oxide makes them electric or mixed electric-ionic conductors, which are of potential interest as cathode materials for solid-state batteries. This glass-ceramics crystallized from the $CuO-V_2O_5-TeO_2$ system are particularly interesting, because they exhibit high conductivity ( up to $6.03{\times}10^{-3}S/cm$) at room temperature. the glass samples were prepared by quenching the melt on the copper plate and the glass-ceramics were heat-treated at crystallizing temperature determined from differential thermal analysis (DTA). The electric D.C conductivity result have been analyzed in terms of a small polaron-hopping model.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.2025-2037
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• 2021

The influence of lead cations on natural quartz (QZ) from Egypt as a glass shielding material for the composition with nominal formula (10Na₂O - (90 - x) QZ - xPbO (where x = 30, 35, 40, 45 and 50 mol %)) was examined. The studied samples are synthesized via the melt quenching method at 1050 ℃. The X-ray diffraction XRD patterns were confirmed the glass nature for studied samples. Moreover, the optical properties, and the transparency for all compositions were examined by UV-Vis spectroscopy. Also, the major elemental composition of the natural quartz were estimated via the X-ray fluorescence (XRF) technique. Further, the density and molar volume were determined. Furthermore, the nuclear shielding parameters such as, mass attenuation coefficient, effective atomic number, electronic density, the total atomic, and electronic cross sections as well as the mean free path, and the half value layer with different gamma ray energies (81 keV-1407 keV) were calculated. Besides, the results showed that the shielding behavior towards the gamma ray radiation for all glass samples was increased as the increment in PbO concentration in the glass system.

• Composites Research
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• 제19권3호
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• pp.15-22
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• 2006

유리섬유로 강화된 폴리프로필렌 복합재료를 이축압출장치를 이용하여 제조하였으며 폴리프로필렌 수지와 유리섬유간의 결합성을 증대시키고 가공성을 향상시킬 목적으로 말레익 안하이드라이드(maleic anhydride) 결합기를 가지는 상용화제를 첨가하였다. 제조된 폴리프로필렌/유리섬유 복합재료에 대한 전단유동과 신장유동의 특성을 조사하였으며, 특히 상용화제 첨가와 유리섬유의 함량에 대한 영향을 주로 평가하였다. 전단유동에서 상용화제는 폴리프로필렌과 유리섬유간의 결합력을 증대시키고, 흐름성을 개선시키는 역할을 하였으며, 신장유동에서는 유리섬유의 함량이 증가됨에 따라서 신장점도를 더욱 증가시켜주는 역할을 하였다. 그러나 신장속도가 증가함에 따라서 유리섬유 사이에서 형성되는 미세한 전단유동의 영향으로 오히려 신장점도는 감소하였다.

• 한국세라믹학회지
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• 제41권12호
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• pp.939-945
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• 2004

[ $SiO_2-B_{2}O_3-Al_{2}O_3-CaO-La_{2}O_3$ ]계 유리에서 $La_{2}O_3$를 변화시키며 다양한 조성의 유리를 만든 후 이를 다공성 알루미나에 침투시켜 알루미나-유리 복합체를 얻었다. 여기서 유리의 조성 변화에 따른 침투특성 및 기계적 강도의 변화를 관찰하였다. 유리중의 $La_{2}O_3$는 유리의 고온 점도를 감소시켜 유리의 젖음성과 유동성을 향상시키고 유리의 침투를 용이하게 한다. 유리가 다공성 알루미나에 침투하여 기공을 메우면서 일부 알루미나를 용해시킨다. 이 유리 용융물 중 $Al_{2}O_3$ 성분은 결정질 알루미나에 다시 석출하여 입자성장이 일어나는데 이때 특정 방향으로 알루미나 입자가 성장한다. $La_{2}O_3$가 20 몰 $\%$ 첨가된 유리를 침투시켰을 때 유리가 결정화하여 복합체의 강도를 증진시켰다.

• 한국세라믹학회지
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• 제44권6호
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• pp.297-302
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• 2007

With aids of square wave voltammetry (SWV) the redox behavior for various combination of polyvalent ions (Sb+Fe, Sb+Zn, Sb+Ce+Ti+Zn) was investigated in alkali-alkaline earth-silica CRT (Cathode Ray Tube) glass melts. The current-potential curve so called voltammogram was produced at temperature range of 1400 to $1000^{\circ}C$ under the scanned potential between 0 and -800 mV at 100 Hz. In the case of the Sb+Fe and Sb+Zn doped melts, peak for $Sb^{3+}/Sb^0$ shown voltammogram was shifted to negative direction comparing to the only Sb doped melts. However, according to voltammogram of Sb+Ce+Ti+Zn doped melt, Ti and Ce except Zn had hardly any influence on the redox reaction of Sb. Based on the temperature dependence of the peak potential, standard enthalpy (${\Delta}H^0$) and standard entropy (${\Delta}S^0$) for the reduction of $Fe^{3+}$ to $Fe^{2+}$, $Sb^{3+}$ to $Sb^0$, $Zn^{2+}$ to $Zn^0$ and $Ti^{2+}$ to $Ti^0$ in each polyvalent ion combination of CRT glass melts were calculated.