• 한국정밀공학회지
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• 제18권11호
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• pp.93-100
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• 2001

Brittle materials are very weak for impact because of typical characteristics which happen to be easily fractured with low fracture toughness and crack sensitivity. When brittle materials are subjected to impact due to small spheres, high contact pressure is occurred to impact surface and then local damage on specimen is developed, since there are little plastic deformations due to contact pressure compared to metals. This local damage is a dangerous factor which gives rise to final fracture of structures. In this research, the crack propagation process of soda lime glass by impact of small sphere is explained and the effects of the constraint conditions of impact spheres and materials for the material damage were studied by using soda-lime glass. that is the effects for the materials and sizes of impact ball, thickness of specimen and residual strength. Especially, this research has focused on the damage behavior of ring crack, cone crack and several kinds of cracks.

• 한국결정성장학회지
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• 제13권5호
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• pp.254-259
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• 2003

Sol-gel dip coating법으로 soda lime glass 기판 위에 ATO(antimony-doped tin oxide) 투명전도막을 제조할 때, 기판 위에 형성된 $SiO_2$ barrier 층 및 $N_2$ gas annealing 에 따른 광투과율 및 전기적 특성에 대한 효과를 정량적으로 측정하고, XPS(X-ray photoelectron spectroscopy) 분석을 통해 고찰하였다. $SiO_2$ barrier층을 갖는 glass 기판 위에 코팅된400 nm 두께의 ATO 박막을 질소분위기에서 annealing한 결과, 광 투과율은 84%그리고 전기저항은 약 $5.0\times 10^{-3}\Omega \textrm{cm}$로 측정되었다 XPS 분석결과 이러한 우수한 전기전도성은 $SiO_2$ buffer층이 glass 기판으로부터 Na 이온의 확산을 막아 ATO막 내에 $Na_2SnO_3$ 및 SnO와 같은 2차상 불순물의 형성을 억제하여 막 내부의 Sb의 농도 및 $Sb^{5+}/Sb^{3+}$ 비를 증가시키고, $N_2$ annealing은 $Sb^{5+}$ 도 환원시키지만 $Sn^{4+}$를 환원시키는 효과가 크게 작용하였기 때문으로 사료된다.

• 한국안광학회지
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• 제5권2호
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• pp.187-192
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• 2000

본 연구에서는 물 유리의 경제성을 바탕으로 광학적 및 기계적인 특성을 조사하여 투명하고 높은 경도를 가진 표면 보호막의 기능을 검토하기 위하여 $SiO_2-Na_2O-R_mO_n$계 박막을 제조하였다. 물 유리에 CaO와 $Al_2O_3$를 소량의 1 N HCl 1N $NH_4OH$와 함께 각각 첨가하여 코팅용 졸을 준비하였다. Stainless steel. Si wafer. soda-lime-silica glass등 다양한 기판 위에 spin-coating 한 후 질소 분위기 하에서 500, 750 및 $900^{\circ}C$로 최종 열처리를 행했다. 제조된 막은 Knoop 경도계로 micro-hardness를 측정하였다. 막의 표면 질소 함유량을 알아보기 위하여 EDX 분석을 행하였다. 그리고 Field Emission Scanning Electron Microscope(FE-SEM)을 이용하여 막의 표면구조를 관찰하였으며, UV-VIS 스펙트라 측정을 통하여 막의 두께와 반사 특성을 조사하였다.

• 한국진공학회지
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• 제16권5호
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• pp.330-337
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• 2007

유전 장벽 방전이 특징인 외부전극 형광램프(External Electrode Fluorescent Lamp, EEFL)에서 유리재의 유전 특성인 유전상수 K와 유전손실 tan ${\delta}$가 램프에 미치는 영향을 조사하기 위하여 4 종류의 유리관을 사용하였다. 종래 일반적으로 사용되는 Borosilicate 유리재는 유전상수 $K=5.6{\sim}5.9$이고 유전 손실 tan ${\delta}=5.0{\times}10^{-3}{\sim}6.0{\times}10^{-3}$이다. Aluminosilicatae는 K=6.6이고 유전손실이 작은 tan ${\delta}=1{\times}10^{-4}$이다. Soda-lime 유리관은 유전상수가 큰 K=7.7이고, 유전 손실이 매우 큰 tan ${\delta}=1.37{\times}10^{-2}$이다. 유전 상수 K가 크면 외부전극 자체의 캐패시터를 크게 하여 방전 효율이 증가한다. 그러나 유전 손실이 크면 외부전극 자체의 전력 소모로 인하여 효율 저하와 핀홀 발생의 원인이 된다. 높은 유전상수 및 낮은 유전손실의 Aluminosilicate 외부전극 형광램프는 종래의 Borosilicate 외부전극 형광램프에 비하여 휘도와 효율이 $12{\sim}20%$ 증가하고, 핀홀에 매우 강하다. 유전상수와 유전손실이 큰 Soda-lime 외부전극 형광램프는 효율이 다소 낮고, 핀홀에도 매우 취약하다. 따라서 외부전극 형광램프는 유전상수 K가 크고 유전손실 tan ${\delta}$가 작은 유리관이 최적이다.

• 한국세라믹학회지
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• 제31권9호
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• pp.957-968
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• 1994

Manufacturing process of porous glass by the filler method was studied. Commercial soda-lime-silicate glass powder was mixed with inorganic salt as the filler such as KCl, K2SO4, Na2SO4. Sintering shrinkages of mixed powders with the variation of sintering temperature were compared, and the effects of the fillers to shrinkages of mixed powder were increased in the order of Na2SO4${\mu}{\textrm}{m}$ of pore diameter were manufactured when the filler sizes 100~200 ${\mu}{\textrm}{m}$. The open pore volume of porous glass is determined by the quantity of filler and porous glasses having open pore volume between 30 and 70 vol% are available. Available sintering temperature range for preparation of porous glass is from the softening temperature of the glass powder to eutectic melting temperature of DTA curve of mixed powder.

• 한국세라믹학회지
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• 제32권5호
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• pp.617-625
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• 1995

In order to reduce reflectance of soda-lime glass having average reflectance of 7.35% and refractive index of 1.53, single (SiO2), double (SiO2/20SiO2-80ZrO2), and triple (SiO2/ZrO2/75SiO2-25ZrO2) layers were designed and fabricated on the glass substrate by Sol-Gel method. Stble sols of SiO2-ZrO2 binary system for antireflective (AR) coatings were synthesized with tetraethyl orthosilicate (TEOS) and zirconium n-butoxide as precursors and ethylacetoacetate (EAcAc) as a chelating agent in an atmosphere environment. Films were deposited on soda-lime glass at the withdrawal rates of 3~11 cm/min using the prepared polymeric sols by dip-coating and they were heat-treated at 45$0^{\circ}C$ for 10 min to obtain homogeneous, amorphous and crack-free films. In case of SiO2-ZrO2 binary system, refractive index of film increased with an increase of ZrO2 mol%. Designed optical constant of films could be obtained through varying the withdrawal rate. In the visible region (380~780nm), reflectance was measured with UV/VIS/NIR Spectrophotometer. Average reflectances of the prepared single-layer [SiO2 (n=1.46, t=103nm)], double-layer [SiO2 (n=1.46, t=1-4nm)/20SiO2-80ZrO2 (n=1.81, t=82nm)], and triple-layer [SiO2 (n=1.46, t=104nm)/ZrO2 (n=1.90, t=80nm)/75SiO2-25ZrO2 (n=1.61, t=94 nm)] were 4.74%, 0.75% and 0.38%, respectively.

• 한국세라믹학회지
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• 제24권4호
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• pp.335-342
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• 1987

There were several numbers of studies on chemically strengthening glass. Most of them were strengthened in molten salt bath below transformation range of glass. Apart from them, this study used solution hydration technique by Autoclave. After determining proper concentration of AgNO3 salt solution, experimental condition varied from 4hrs to 16hrs at relatively low temperature (180, 200, 220$^{\circ}C$). The results showed that the Soda-Lime-Silica glass could be strengthened by diffusion mechanism without influence of water above 15% salt solution. Because of Ag+ ion penetration in glass surface, yellow color appeared and decreased transmittance at visible range. Modulus of rupture was increased with the amount of exchange and brittleness was decreased.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.640-643
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• 2003

We present investigations of the surface micromachining for transparent glass substrate, e.g. soda lime glass using tightly focused 800nm Ti:sapphire femtosecond laser. In this study, experiment conditions such as laser intensity, scanning speed, focus position were controlled as variable parameters to decide optimal machining conditions. This study shows clearly that laser intensity and scanning speed are dominant factors for good surface morphology. Using the optimal conditions, grooves with 50${\mu}{\textrm}{m}$ line width were fabricated on glass substrate and their surface morphologies were investigated from SEM image.

• 한국기계가공학회지
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• 제13권6호
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• pp.145-151
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• 2014

The glass used for mobile display windows is required to have high strength. Chemical strengthening by means of ion exchange is widely used glass. The depth of the layer and the compressed stress are affected by tempering temperature and time. The purpose of this study is to investigate the range of DOL and CS, which to less breakage during reliability tests such as the ball drop test, hole drop test, 3-point bending test, drop test, and tumble test with Soda-lime Glass.

• 한국전기전자재료학회논문지
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• 제21권8호
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• pp.755-759
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• 2008

For the development of a new white dielectric layer in plasma display panel, different $TiO_2$ types as a filler was add to the $Bi_2O_3$-BaO-ZnO glass matrix. The reflectance and dielectric constant of dielectric have been investigated as a function of the mixing content (rutile and anatase), and sintering temperature. The reflectance of dielectric sintered at the 520$^{\circ}C$ appeared most highly and suitable in terms of the adhesion and reflectance of the soda-lime glasses. Also, the thermal expansion coefficient of dielectric was found to be $85.6\times10^{-7}/K$, which was similar to that of the soda-lime glasses. Especially, the dielectric constants were not increased with increasing of $TiO_2$ filler contents.