• Textile Coloration and Finishing
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• v.4 no.1
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• pp.16-20
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• 1992

This study was to examine the dry cleaning resistance of chrome bonding in the chrome-tanned garment leathers, and to analyze their chrome content. The results are as follows: 1. The average percentage of the chrome content (as $Cr_2O_3$) in the chrome-tanned garment leathers was 2.7%. 2. By the dry cleaning treatment and its numbers, the values of chrome content were little affected. 3. The resistance against dry cleaning with perchloroethylene $(Cl_2C = CCl_2)$ of samples was confirmed.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.245-246
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• 2017

현대인의 필수품이 되어버린 인터넷을 편리하게 활용할 수 있는 다양한 실용사례와 연구가 진행되고 있다. 본 연구는 수많은 웹 브라우저 중에서 사용자들의 가장 많은 활용하고 있는 Google사의 Chrome 웹 브라우저에서 다양한 기능들을 탑재시켜 인터넷 사용을 더욱 효율적으로 지원할 수 있는 Extension 기능을 소개한다. 또한 본 기능을 개발자들이 활용하여 다양한 응용 프로그램들을 탑재시켜 인터페이스를 향상할 수 있도록 구현한 사례를 소개한다. 본 시스템을 통해 웹 브라우저의 추가적인 부가기능과 사용자의 편의성을 더욱 발전시킴으로써 사용자들에게 도움이 될 것으로 기대하고 있다.

• The korean journal of orthodontics
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• v.15 no.2
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• pp.163-174
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• 1985

The requirements of orthodontic wire should include chemical stability, non-discoloration and non-corrosion in oral environment. Ability to be soldered, ease of fabrication and elasticity should be also considered. The purpose of this study was to compare and analyze the physical properties of Tru-chrome wire and manufactured E.S.S. (Experimental Stainless Steel) wire similar to Tru-chrome. The results were as follows: 1. Tru-chrome wire and E.S.S. wire were SUS 304 which was 18 Cr-8Ni austenite stainless steel. There was not significant difference in each composition between two wires. 2. There were not significant differences in ultimate tensile strength, yield strength, elongation and modulus of elasticity between Tru-chrome and E.S.S. wires. 3. There was not significant difference between flexuree modulus of elasticity of Tru-chrome and E.S.S. wires. 4. Micro-hardness value of E.S.S. wire was more than that of Tru-chrome wire and they were softened significantly by solution heat reatment. 5. Micro-structure of Tru-chrome and E.S.S. wires showed fibrous interlocking grains, and an austenite structure after solution heat treatment. 6. There was significant difference between corrosion rate of Tru-chrome and E.S.S. wires.

• Korean Journal of Metals and Materials
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• v.47 no.2
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• pp.99-106
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• 2009

The high temperature corrosion properties of heat resistant steels were investigated in oxidation atmosphere including sulfur dioxide. The heat resistant steels of T22, T92, T122, T347HFG and T304H were evaluated at 620, $670^{\circ}C$ for 400 hours. The corrosion rates showed a decreasing tendency while chrome contents of those steels increased from 2 mass.% to 19 mass.%. The in crease in temperature increasement has an more effect on the corrosion rates of low chrome steels than high chrome steels. The weight gains of T22, T92, T304H at $670^{\circ}C$ were 3.7, 1.65, 1.23 times compared with those at $620^{\circ}C$. The external scale formed on T22 was composed of hematite, magnetite and Fe-Cr spinel and internal layer including iron oxide mixed with sulfide. The scales formed on T92, T122, T304H consisted of an outer layer of hematite and inner layer of chrome oxide and hematite. The proportion of chrome oxide at inner layer was increased when the chrome contents in heat resistant steels were increased.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.36-36
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• 2002

Effects of pulse-plating on the wear and corrosion resistance of chrome-carbon layers were studied. The plating were carried out at $06A/\textrm{cm}^2$ in modified Sargent bath containing formic acid at $53^{\circ}C$. The chrome layer were super-saturated with carbon up to 2.0wt. %, which precipitated as chrome carbide such as $Cr_{23}C_6$ after vacuum aging above $200^{\circ}C$ for 1 hour. This resulted in improvement of hardness and wear resistance of the chrome layer. Considering the reduction of corrosion resistance due to the thermal effect, optimum vacuum aging condition of the chrome layer in this study was I-hour at $200^{\circ}C$.

• Journal of Korean Society for Quality Management
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• v.45 no.3
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• pp.327-333
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• 2017

Purpose: The purpose of this study is to research to protect to loss of chrome-plating of small arms barrel on high temperature in order to extend its life expectency. Methods: The reason why chrome-plating dropped out is main material is weak from heat. Therfore, to make barrel of small arms have higher heat-resistant property, nitriding for barrel before chrome-plating is needed and test of that barrel was handled to improve it. Results: Nitriding before chrome-plating is useful to protect to chrome-plating loss on high temperature. Conclusion: To protect loss of chome-plating of small arms barrel during on firing, pre-nitriding on barrel is effective finally it leads to extend to barrel's life expectency.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.1
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• pp.9-15
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• 2005

The polariscope to measure the microscopic stress in CR lens consists of light source polarizer, model, polarizer, CCD, computer, chrome conversion orderly and the principal-stressed difference, (${\sigma}_1-{\sigma}_2$) and the fringe order n were measured by analyzing two components of light wave $E_1$ and $E_2$ following each polarizer's steps. The two-dimensional model could be determined from the fact that the optical axes of sample concide with the principal-stress directions. The bi-refringence acted to a light wave and the phase retardation were in proportion to the principal-stressed difference(${\sigma}_1-{\sigma}_2$) and the intensity of final light wave was proportioned to $sin2({\Delta}/2)$ and when ${\Delta}/2=n{\pi}$ (n=0, 1, 2, ${\ldots}$) the extinction occurs. Photoelastic's image by microscopic stress could analyzed using chrome conversion, and the image showed clearly.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.6
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• pp.97-101
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• 1998

In this study, The ultra-precision finishing system is applicable to all kind of the cylnderical workpiece products fast and easy. This system was applied to chrome coated steel to investigate the characteristic of grinding; (1) 3$mu extrm{m}$ of abrasive film is not use for grinding performance. (2) Grinding condition of coated chrome steel would set up differently, in 30~12${\mu}{\textrm}{m}$, in 9~5${\mu}{\textrm}{m}$. (3) The surface roughness of chrome coated steel was about Ra 0.0009${\mu}{\textrm}{m}$ in abrasive grain size 5${\mu}{\textrm}{m}$.

• Journal of Korean society of Dental Hygiene
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• v.13 no.2
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• pp.361-368
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• 2013

Objectives : The purpose of this in vitro study was to evaluate the effect of firing cycles on the marginal and internal fit of metal ceramic crown. Methods : Ten same cases of stone models (abutment teeth 11) were manufactured. Ten cobalt-chrome cores were made per each models and the marginal and internal fit was evaluated through a silicone replica technique. The marginal and internal fit of specimens was measured twice. The first measurement was done after manufacturing cobalt-chrome alloy core and the second measurement was done after porcelain firing. T-test of paired sample for statistical analysis was executed with SPSS 12.0K for Windows (${\alpha}$=0.05). Results : Mean(SD) marginal and internal fit were 77.1(23.3) ${\mu}m$ for the cobalt-chrome alloy core group and 84.4(21.9) ${\mu}m$ for the metal-ceramic crown group. They were statistically significant differences between groups for marginal and internal fit (p<.05). Conclusions : All metal ceramic crowns showed marginal and internal fit ranged within the current clinical recommendations.

• Solar Energy
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• v.7 no.2
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• pp.65-73
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• 1987

Microstructural basis for the thermal degradation of electrodeposited black chrome "solar-L-foil" heated in air has been investigated using scanning electron microscopy, energy dispersive x-ray analysis, X-ray diffraction techniques and UV-VIS-NIR spectre-photometer. Experimental result, the change in the shape of the particle comprising the film from their initial needle like structure to a more spherical shape with an oxide after 1hr annealing at $600^{\circ}C$ has been observed. The effect is to degrade solar absorptance of the thin film.