• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.2
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• pp.98-102
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• 2004

Ion exchange behavior and property change of soda-lime-silicate glass by advanced ion exchange process were investigated. Refractive index, specific gravity and optical transmittance were changed similarly to $K^+$ ion penetration depth, and amount of ion exchange increased with the increase of the time and temperature. Especially, thermal expansion decreased greatly because of the structural compaction and residual stress by ion exchange process.

• Journal of the Korean Ceramic Society
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• v.52 no.2
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• pp.133-136
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• 2015

The outward diffusion of $Na^+$ ions in iron-bearing soda lime silicate glass via oxidation heat treatment before the ion exchange process is artificially induced in order to increase the amount of ions exchanged during the ion exchange process. The effect of the addition process is analyzed through measuring the bending strength, the weight change, and the inter-diffusion coefficient after the ion exchange process. The glass strength is increased when the outward diffusion of $Na^+$ ions via oxidation heat treatment before the ion exchange process is added. For the glass subjected to the additional process, the weight change and diffusion depth increase compared with the glass not subjected to the process. The interdiffusion coefficient is also slightly increased as a result of the additional process.

• Journal of the Korean Ceramic Society
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• v.52 no.2
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• pp.137-139
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• 2015

In this study, we examined the influence of molten $KNO_3$ flow on mechanical properties and their deviation when a chemical toughening process was applied to soda lime silicate glass ($Na_2O-CaO-SiO_2$). $KNO_3$ melt flow was controlled using three methods: (1) glass tray rotation, (2) impeller stirring, and (3) natural convection. DOL and hardness were found to be enhanced by tray rotation because this rotation was able to maintain the concentration around the glass surface, in contrast to other methods. However, there did not appear to be a statistically significant difference in the 3-point bending strength for the three flow conditions due to the ground edge condition.

• Journal of the Korean Ceramic Society
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• v.56 no.5
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• pp.483-488
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• 2019

We studied whether chemical strengthening can heal the flaws on soda-lime silicate glass. Artificial surface cracks were introduced on the glass by sharp indentation with various loads of 0.1 to 10 N. Then, the glasses with flaws were treated by ion-exchanging in KNO₃ melt. The change in the dimension of the crack on glass was measured by a digital microscope and a scanning electron microscope. The chemical strengthening treatment enhances the strength of the glass with flaws. It is thought that the melted KNO₃ not only forms the depth of the compressed layer of 7.5 ㎛, but also heals the cracks by infiltrating them and expanding the glass on both sides of the cracks. The critical length (2c) of the cracks on soda-lime glass that can be healed by chemical strengthening is 50 ㎛ or less.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.367-370
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• 2007

An EEFL with the sodium free alumino-silicate glass of high K and low $tan{\delta}$, has been investigated. As compared with borosilicate and the soda-lime EEFLs, the luminous efficiency as well as the pinhole stability of new EEFLs improves remarkably without blackening of $NaHg_2$.

• Journal of the Korean Ceramic Society
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• v.52 no.2
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• pp.123-127
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• 2015

Soda-lime silicate (SLS) glass was strengthened by ion exchange for application of thin and lightweight bulletproof windows. The optimal conditions for ion exchanged SLS glass (thickness of 3 and 10 mm) at $480^{\circ}C$ were 10 and 17 min, respectively. The Vickers hardness values of the strengthened SLS glass samples with thicknesses of 3 and 10 mm were $5.9{\pm}0.22$ and $6.7{\pm}0.17GPa$, respectively, which values were about 22% higher than those of parent SLS glass. By laminating a multilayer defense film and polycarbonate sheet with ion exchanged SLS glass, we were able to make a thin and lightweight bulletproof window (24.25 mm, 4.57 kg, $50.06kg/m^2$, $V_{50}$ 901.8 m/s). As a result, the thickness of the bulletproof window was decreased by about 39% from 40 to 24.25 mm. The light transmittance in the visible range satisfied the standard (over 76%) for bulletproof windows.

• Journal of the Korean Ceramic Society
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• v.39 no.7
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• pp.675-679
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• 2002

To produce a strengthened glass, single ion exchange properties such as three-point bend strength and residual stress were investigated in soda-lime-silicate substrate glass for display use. The present work showed that the maximum value of strength was 62.5${\times}$10$\sub$6/ kg/㎡ after, the two-step single ion exchange process at 470$^{\circ}C$ for 1 h and 450$^{\circ}C$ for 24 h. As the result of the fracture analysis after bending test, the residual stress on the fractured surface of the strengthened glass increased the flexibility by means of absorbing the elastic deformation energy in the glass. Also, the effects of absorbing the elastic deformation energy were analysed by curvature change, number of multiple crack branches and brittleness.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.382-390
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• 2013

Foaming process of waste soda lime glasses by just chemical composition control of vitreous feed materials was investigated to find a novel and efficient recycling process. For the chemical composition control of feed materials, 10 wt. parts of $SiO_2$, 0.5 wt. parts of $Na_2SO_4$, 3.0 wt. parts of $B_2O_3$, and 0.3 wt. parts of carbon black as the foaming agent were mixed with 100 wt. parts of soda-lime vitreous feed powder. Proper conditions for foaming process in tunnel kiln are the foaming temperature of $830{\sim}850^{\circ}C$, the foaming time of 30~35 min, and the vitreous feed powder particle size of -325 mesh. Properties of foamed glass blocks obtained under these foaming conditions showed the density of $0.17{\sim}0.21g/cm^3$, thermal conductivity of $0.06{\pm}0.005kcal/h{\cdot}m{\cdot}^{\circ}C$, moisture absorption of 1.1~1.5%, and compressive strength of $20{\sim}30kgf/mm^2$.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.1
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• pp.114-119
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• 2010

There are a number of studies on chemically strengthened glass. Most of them are strengthened in molten salt bath below transformation range of glass. This research is distinguished from the aforementioned studies in that single $KNO_3$ powder was used by employing screen printing technique. In this study soda-lime-silicate(SLS) glasses for bulletproof glass application with various thicknesses were used. The maximum value of the bending strength is 791MPa heat treated at $480^{\circ}C$, which is about 4.3 times higher than the parent glass, which is the highest strength of all soda-lime glasses. In this study, it is also observed that Vickers hardness increased to $657H_v$, which is about 15% higher than the parent glass($568.7H_v$) and fracture toughness was not changed. Depth profiles measured by electron probe micro analyzer(EPMA) showed a correlation between the migrations of $K^+$ ions with bending strength of ion exchanged glasses.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.6
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• pp.91-98
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• 1992

In the research on the fracture time of soda lime silicate glass under thermal shock, it is shown that the theoretical and experimental fracture times are in good agreement, the suggested method to measure critical stress intensity factor for small three-point bending specimen is useful and the edge temperature before thermal shock on cracked side vs. crack length and fracture time are inversely proportional.