• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.25-28
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• 1998

In this study, we investigated the electrical characteristics of silicone rubber that being used outdoor insulating material, which had been immersed in salt water. After immersed the sample in salt water, we measured surface hydrophobicity, weight loss and microscopic surface appearance, and then compared with these of the original. And we tested the electrical characteristics of the aged sample by the water under salt-fog. These electrical characteristics are described by the average of leakage current, peak pulse number, which are recorded by data acquisition system The experimental results show that the resistance against tracking and erosion is decreased significantly by water penetration.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.9
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• pp.1764-1768
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• 2009

As the demand of electric power is increasing rapidly, the need of the compact and light electric power device is also increased. Copper clad aluminum (CCA) is newly proposed electrical conductor, because of its light-weight and low-cost characteristics, to replace the existing conductor made of copper. This paper presents the salt-proof characteristics of the copper clad aluminum (CCA) to certificate long time safe operation of the newly proposed electrical conductor. The two types of the CCA conductor were tested in the neutral salt spray tester. The experimental results of two types of the CCA with salt spray were presented in this paper. The results comprise resistance measured data, micro picture of the selected surface, and component measured data according to the elapsed time. The period of the experiment was 1,000 hours. There was no evidence to show the corrosion of CCA during the whole period of the experiments.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.207-208
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• 2010

The building that supply tidal and splash zone was constructed near Seamangeum Gate Bridge. The specimens that will be tested for maintenance of gate bridge were exposed on the tidal and splash zone, totally about 650. The characteristics of strength, salt penetration profile, field application of surface repair material and section recover material will be acquired by periodical test. The program was developed to obtain optimal maintenance strategy of gate bridge as a marine concrete structure and to deposit experimental data, lab. test result, field test result, on its D/B. On this paper, the comparison of concrete and recover material in the salt penetration characteristics was expressed. The quantitative analysis of salt contents in concrete surface was most important so the improvement for the machine of gathering power of concrete and the apparatus of measuring chloride contents was proceeded at this time. The two conclusions were summarized like as - The resistance of chloride attack of concrete was appeared 2.5 times bigger than that of recover material - The resistance of chloride attack of polymer series was appeared more higher than that of others.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.271-272
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• 2006

Zinc confers high corrosion resistance by acting as a sacrificial anode, and a zinc coating improves the appearance of steel. Chromate conversion coating (CCC) films are still one of the most efficient surface treatments for steel. Although such films can self-repair via the dissolution of Cr(VI), dissolved Cr(VI) have adverse effects on humans, and the environment. Therefore, we examined the corrosion protection property and morphology of colloidal silica conversion films as an alternative to CCC films. The corrosion behavior was investigated in 3% NaCl solution using electrochemical techniques, including electrochemical impedance spectroscopy, open circuit potential, and the salt spray test(SST). Corrosion was implied by the appearance of red rust on the specimen surface. In corrosion resistance at 3% NaCl solution, red rust appeared at 15-20, 55-70, and 83-98 days on Zn-electroplated steel, colloidal silica conversion-coated specimens, and CCC-coated specimens, respectively. In the salt spray test, the colloidal silica film provided better corrosion protection than CCC films, i.e., red rust appeared at 96 hours on the Zn-electroplated steel sheet, at 432 hours with the CCC films, and at 888 hours with silica conversion coating.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.265-266
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• 2006

The chemical conversion coating formed on magnesium alloy investigated for low cost and harmless in environment by using the colloidal silica as the main component. The film formed in 298 K is thick, the film, which was thought combination of Si-O, was formed. The film formed in 313 K is thinner than that in 298 K. The quantity of film formed at high temperature such as 333 K and 353 K is smaller than dissolved quantity. At the anodic polarization experiment, corrosion resistance in sealing by hot water after chemical conversion treatment in basic solution condition get worse than that in comparison with basic solution condition. In salt spray test, the ratio of black rust on specimen that did not conducted chemical conversion treatment was five times or more compared with those of chemical conversion treated specimen. The film thickness of chemical conversion coating produced by alkali treatment process is thinner than in comparison with that of specimen produced in basic chemical conversion treatment solution condition. It is thought, however, that it showed good corrosion resistance during salt spray test because the area of microcracks is small.

• Corrosion Science and Technology
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• v.10 no.6
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• pp.199-204
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• 2011

Hot dip metallic coated steels like as galvanized (GI), zinc-aluminium (GL) and aluminium coated steels are mostly used where corrosion resistance is needed. There are two kinds (type 1 and type 2) of aluminium coated steel being commercially used among them. Type 1 aluminium coated steel is coated with an Al-5~11 wt%Si alloy and Type 2 aluminium coated steel consists of commercially pure aluminium. Type 1 Al coated steel is generally used in automotive components and electrical appliances while type 2 aluminium coated steel is mainly used in construction applications such as building cladding panels, air conditioning and ventilation system. In this study, Type 1 aluminium coated steels have tested by accelerated conditions (salt spray or corrosive gas) and outdoor exposure condition in order to understand their corrosion behaviour. Due to the distinct corrosion mechanism of Al which exposes to the severe chloric condition, Salt Spray Test cannot predict the ordinary atmospheric corrosion of Al based coated materials. In addition, the test results and their corrosion feature of Al coated steel sheets will be discussed comparing with other metallic coated steel sheets of GI and GL.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.22 no.1
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• pp.67-80
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• 2024

Fundamental aspects of creating passivation layers for corrosion resistance in nuclear engineering applications, specifically the ability to form complete layers versus porous ones, are being explored in this study. Utilizing a laser ablation technique, 1,064 nm fire at 10 Hz with 60 pulses per shot and 0.5 mm between impact points, aluminum samples are treated in an attempt to create a fully formed passivation layer that will be tested in a LiCl-KCl eutectic salt. By placing these samples into an electrochemical environment mimicking a pyroprocessing system, corrosion rates, resistances and material characteristics are tested for one week and then compared between treated and untreated samples. In initial testing, linear sweep voltammetry indicates corrosion current density for the untreated sample at -0.038 mA·cm^-2 and treated samples at -0.024 mA·cm^-2 and -0.016 mA·cm^-2, respectively. This correlates to a control sample corrosion rate of -0.205 mm·yr^-1 and treated rates of -0.130 mm·yr^-1 and -0.086 mm·yr^-1 for samples 1 and 2. In addition, electrochemical impedance spectroscopy circuits show application of a longer-lasting porous passivation layer on the treated metal, compared to the naturally forming layer. However, the current technique fails to create a uniform protection layer across the sample.

• Magazine of the Korea Concrete Institute
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• v.6 no.6
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• pp.173-179
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• 1994

Epoxy coated bars protecting reinforcing bars from corrosion and enhancing durability of reinforced concrete structures are tested to evaluate corrosion protection properties. Tests are performed based on the relevant sta.ndards of KS and ASTM, such as chenical resistance, salt water spray, salt crock test and chloride ermeability test. with the main varlable of the coating thlckness. Test results show good chemical protection property and chloride permeability. The results of the salt water spray and the salt crock test show that epoxy coating well protects the reinforcing bars from corrosion, cornparing to the biack bars without epoxy coatmg. However, several spots on the coated bars are rusted at the pinholes or un the bars with coating thickness less thar $200{\mu}M$. Special cautions are required i n the process of blast cleanmg when applying the usion-bonded epoxy coating.

• Korean Journal of Materials Research
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• v.14 no.4
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• pp.251-259
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• 2004

In the development of the advanced spent fuel management process based on the molten salt technology, it is essential to choose the optimum material for the process equipment handling molten salt. Corrosion behavior of Ni 200 and Ni-base alloys in molten salt of LiCl-$Li_2$O under oxidation atmosphere was investigated in the temperature range of $650～800^{\circ}C$ for 24～312 hrs. The order of corrosion rate was Ni 200 > Inconel 690 > Inconel 601 > Inconel 600. Inconel 600 alloy showed the highest corrosion resistance among the examined alloys, but Ni 200 exhibited the highest corrosion rate. Corrosion products of Inconel 600 and Inconel 601 were $Cr_2$$O_3$ and $NiFe_2$$O_4$. In case of Inconel 690, a single layer of $CrO_2$$O_3$ was formed in the early stage of corrosion and an outer layer of $NiFe_2$O$_4$ and inner layer of $Cr_2$$O_3$ were formed with increase of corrosion time. Inconel 600 showed local corrosion behavior and Inconel 601, 690 showed uniform corrosion behavior.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.72-80
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• 2007

This study was carried out to investigate the effects of various salts on the physical and fermentative characteristics of doughs and on the quality of white pan breads produced using purified salt, Korean solar salt, Chinese solar salt, Mexican solar salt, washed and dehydrated salt, roasted salt, and bamboo salt. In farinogram patterns, dough prepared using the purified salt had the highest water absorption. Extensograms showed that the resistances and resistance/extensibility ratios of the doughs with the solar salts were higher than those with the purified salt. In amylograms, the dough with the bamboo salt had the highest viscosity value. A specific volume was the smallest in the bread with the Korean solar salt (4.11 mL/g), while the largest with the Mexican solar salt (4.85 mL/g). A baking loss rate of the bread prepared with the Korean solar salt (10.34%) was less compared to other samples (10.91 $\sim$ 11.65%). The crust of the bread added with the Korean solar salt showed higher L value and lower a value while its crumb showed the highest b value. A sensory evaluation indicated that significant differences in some characteristics of the breads were observed in the breads prepared with the Korean solar salt and Mexican solar salt. However, flavor, taste, and overall acceptability showed no significant differences among all breads prepared with different salts.