• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.196-200
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• 1996

In the case of construction under the marine environment the durability of concrete structures is everely deteriorated by the penetration of salts which results in the corrosion of reinforcing steel. To verify the effect of corrosion protection of reinforcing steel by isolating the penetration of chlorideion this study investigated the bond strength between painting material and concrete, the degree of the penetration-diffusion of chloride ion and the accelerated corrosion test using different potential. Results show that the painted concrete has little the penetration-diffusion of cholride and the reinforcing steel in painted concrete is little corroding.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.191-196
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• 1997

Steel is the most used as materials for construction and corrosion expansion of steel due to outdoor corrosive environmental factor bring serious problem on the durability of concrete structures time after time. It is the purpose of this study to see whether it is effective of not, when sacrificial anode method is adapted. Indoor accelerated corrosion testing was carried out to see its effective in a short term. From the mid result, potential of steel in concrete in case of adapting sacrifice anode method satisfacts protection standard value (less than-850mV vs CSE), therefore sacrificial anode method is considered as a proper protection steps against corrosion of steel.

• Corrosion Science and Technology
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• v.6 no.5
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• pp.239-244
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• 2007

Corrosion protection of automotive steels has traditionally been assured by using a zinc phosphate metal pretreatment followed by the deposition of a cathodic electrocoat system. This system has been developed and optimized over the years into a highly robust and dependable system with a high performance. However, in terms of efficiency and use of resources and energy, the need is now felt to develop a simpler system with fewer steps, shorter lines, less energy requirements (curing and e-coat deposition) and less stringent waste disposal requirement (phosphate sludge). We report here on the development of a one-step system that can possibly replace both the zinc phosphate and the e-coating processes. Such a system is based on the so-called superprimer concept that we have recently developed for the replacement of chromate pretreatment and chromate-containing primers in the aerospace industry. With some modifications, such systems can also be adapted for use in the automotive industry.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.270-275
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• 2010

Technical issues of steel industry change along with other industrial progresses. Traditionally, steel protection from corrosion environment was the major issue and galvanic metal coatings were mainly used to extend the lifetime of steel products. Nowadays, requirements for steel have become more diversified. More various surface and material properties are required from different field of applications. Naturally, functional surface coating has become one of the most studied areas in steel industry. For functional surface coating, various process technologies and coating products are investigated. In this article, recent trends of functional coating technologies and products are introduced with brief technical descriptions of representative coating products.

• Corrosion Science and Technology
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• v.4 no.6
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• pp.242-249
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• 2005

A lot of parts in FGD (Flue Gas Desulfurization) systems of fossil-fuel power plants show the environments in which are highly changeable and extremely acidic corrosive medium according to time and locations, e.g. in duct works, coolers and re-heaters etc. These conditions are formed when system materials are immersed in fluid that flows on them or when exhausted gas is condensed into thin layered acidic medium to contact materials of the system walls and roofs. These environments make troublesome corrosion and air pollution problems that are occurred from the leakage of the condensed solution. To cathodically protect the metallic structures in extremely acidic fluid, the properties of the protective coatings on the metal surface were very important, and epoxy Novolac coating was applied in this work. On the base of acid immersion tests, hot sulfuric acid decreased the hardness of the coatings and reduced greatly the content of $Na_2O$, $Al_2O_3$, and $SiO_2$ among the main components of the coating. A special kind of CP(Cathodic Protection) system has been developed and tested in a real scale of the FGD facility. Applied coating for this CP system was peeled off and cracked in some parts of the facility. However, the exposed metal surface to extremely acidic fluid by the failure of the coatings was successfully protected by the new CP system.

• Journal of Ocean Engineering and Technology
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• v.21 no.3 s.76
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• pp.65-70
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• 2007

There are many kinds of protection methods for marine structures, with varyingeconomical and environmental advantages. The coating protection method is being widely used in both continental and marine structures. In this study, by adding some additives, such as Zn powder(Zn), carbon black(CB) to epoxy anti-corrosive paint, the effect on the corrosion resistance was investigated throughan electrochemical method. The additive of Zn(20)+CB(10) showed the lowest passivity current density. Polarization resistance in both cyclic voltammogram and impedance measurement of an additive of Zn(20)+CB(10) was also the largest value, compared to other additives. Furthermore, rusting and bubbling was not observed on the surface of the test specimen with the additive of Zn(20)+CB(10), compared to other specimens. It is suggested that the corrosion resistance of the anti-corrosive paint can be improved by using some additives.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.249-254
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• 2004

The pressing of car body parts is one of the most important sheet metal drawing processes. The corrosion protection oil applied by the steel mills plays a part in every sheet metal forming operation and also makes up the largest proportion of lubricants used. The idea to combine the corrosion protection properties of a corrosion preventive oil with the lubricity of a drawing oil lead to the development of the Anticorit prelubes. Applied at the finishing lines of the steel mills, they finally serve as lubricant in the press shops. A prerequisite for the suitability of a prelube-type oil is the absolute compatibility with all single processes from the coil to the Body in White. The use of prelubes in steel mills reduces the number and quantity of spot lubricants for additional press shop oiling dramatically. But their true benefits can only be fully achieved if the compatibility principle is applied throughout the manufacturing chain. Therefore, modem prelubes systems are modular, even different viscosities can be part of the same concept. This results in a far-reaching multifunctionality of the Anticorit prelube system for all applications.

• Journal of the Korean Institute of Gas
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• v.13 no.2
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• pp.1-6
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• 2009

With respect to a given structure, a stray current is to be defined as a current flowing on a structure that is not part of the intended electrical circuit. Most often DC-powered traction systems like railroads and tramlines are responsible for large dynamic stray currents. This type of stray current is generally results from the leakage of return currents from large DC traction systems that are grounded or have a bad earth-insulated return path. At the place where the current leaves the rail and metallic structures, electrolytic corrosion may take place. This paper investigates the domestic conditions on the electrolytic corrosion protection of buried metallic structures adjacent to DC traction systems by survey.

• Corrosion Science and Technology
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• v.6 no.6
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• pp.269-274
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• 2007

The corrosion of steel in concrete is significant in marine environment. Salt damage is one of the most detrimental causes to concrete bridges and port structures. Especially, the splash and tidal zones around water line are comparatively important in terms of safety and life-time point of view. During the last several decades, cathodic protection (cp) has been commonly accepted as an effective technique for corrosion control in concrete structures. Zn-mesh sacrificial anode has been recently developed and started to apply to the bridge column cp in marine condition. The detailed parameters regarding Zn-mesh cp technique, however, have not well understood so far. This study is to investigate how much Zn-mesh cp influences along the concrete column at elevated temperature. About 100 cm column specimens with eight of 10 cm segment rebars have been used to measure the variation of cp potential with the distance from Zn-mesh anode at both $10^{\circ}C$ and $40^{\circ}C$ in natural seawater. The cp potential change and current diminishment along the column specimens have been discussed for the optimum design of cp by Zn-mesh sacrificial anode.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.173-176
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• 2006

There are many kinds of protection methods for marine structures by using and environmental condition. Coating protection method, one of these methods is being widely adopted to both all ground and marine structures. In this study, by adding some additives such as Zn powder(Zn), carbon black(CB) to epoxy anti-corrosive paint, the effect to promote corrosion resistance was investigated with electrochemical method. Corrosion potentials with additives shifted to negative direction than no additive. However passivity current density increased than no additive except for Zn(20)+CB(10), especially, additive of Zn(20)+CB(10) showed the smallest passivity current density. Polarization resistance of Zn(20)+CB(10) by both cyclic voltammogram and impedance measurement was the largest value than other additives. And also surface phenomenon by adding Zn(20)+CB(10) was observed a good add condition not showing bubbling than other additives.