• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.221-223
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• 2011

In this study, in order to comprehend performance of corrosion inhibitor, the experiment study was conducted about corrosion characteristic of 3 steps(0.0, norm 1/2, norm) compared to organic corrosion inhibitor standard use of liquid and molar 3 steps(0.0, 0.3, 0.6%) of Chloride by added amount of inorganic corrosion inhibitor by the corrosion inhibitor types about 2.4kg/㎥, 4.8kg/㎥ based on Chloride ion content 1.2kg/㎥ for service life prediction of concrete structure by using Poteniostat.

• Corrosion Science and Technology
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• v.11 no.1
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• pp.15-19
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• 2012

Both electrogalvanized and hot-dip galvanized steel sheets have been finally produced via organic-inorganic surface coating process on the zinc surface to enhance corrosion resistance and afford additional functional properties. Recently, POSCO has been developed a variety of chromate-free coated steels that are widely used in household, construction and automotive applications. New organic-inorganic hybrid coating solutions as chromate alternatives are comprised of surface modified silicate with silane coupling agent and inorganic corrosion inhibitors as an aqueous formulation. In this paper we have prepared new type of hybrid coatings and evaluated quality performances such as corrosion resistance, spot weldability, thermal tolerance, and paint adhesion property etc. The electrogalvanized steels with these coating solutions exhibit good anti-corrosion property compared to those of chromate coated steels. Detailed components composition of coating solutions and experimental results suggest that strong binding between organic-inorganic hybrid coating layer and zinc surface plays a key role in the advanced quality performances.

• Journal of the Semiconductor & Display Technology
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• v.6 no.2 s.19
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• pp.25-28
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• 2007

Electroless Ni-P coating is widely used for chemical, electronic, and semiconductor equipment parts because of its corrosion resistance. The incorporation of chemically-inert PTFE particles into the Ni-P films improves properties such as, non-stick, anti-adhesive and better corrosion resistance. However, soft PTFE particles degrade the hardness, wear and abrasion resistance. In this study, effects of PTFE and W addition to the Ni-P-coatings were compared by the XRD, SEM, sheet resistance, contact angle, and microhardness measurements. The change in sheet resistance was negligible, but contact angle was doubled by the addition of PTFE and W. The microhardness was lower for Ni-P-PTFE, but higher for Ni-P-PTFE-W coatings, compared to that of Ni-P coatings.

• International Journal of Korean Welding Society
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• v.2 no.1
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• pp.62-66
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• 2002

The Friction Stir Welding (FSW) is a new joining method that was developed at The Welding Institute (TWI) in England in 1991. It applied heating by the rotational friction and material plastic flow. It was developed as a new joining method to solve the problems of epochally in the welding of Al alloys. In the study, 6000series of Alloy composed of Al-Mg-Si, one of the Al alloys that are utilized for shipbuilding and construction, is selected as a specimen and the numerical is executed against the welded zone of FSW. The material used in this study had the unique properties of strength and anti-corrosion, but since the welded joint of this material is easily softened by the welding heat, FSW is executed and the numerical analysis is carried out around the joint. To examine the mechanical behaviors and properties, F.E.M analysis is executed and the developed thermal-elastic-plastic finite analysis are used.

• Journal of the Korean institute of surface engineering
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• v.31 no.6
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• pp.379-388
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• 1998

The iron-zinc interfacial reaction and corrosin properties in galvanizing bath containning Ni have been intestigated. The substrate steel plates were galvanized in Zn or Zn-0.018Al baths with various Ni contents. The corrosion resistance of galvanized specimens was also evaluated by $60^{\circ}$bending test for galvannealing speaaimens. The corrosion resistance was improved with Ni addition in pure Zn bath, while deteriorated with Ni addition in Zn-0.18Al bath. The anti-powdering property, on thhe otherhand, was improved with Ni addition in Zn-0.18Al bath, while deteriorated with Ni addition in pure Zn. It was found that the anti-powdering property was improved with increasing $\xi$ phase ratio in reaction layer.

• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.3-10
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• 2005

The purpose of this study is to investigate the properties of composite systems using polymer cement and epoxy resins for waterproofing and anti-corrosion to concrete structures such as water supply facilities and sewage-works. For the waterproofing and anti-corrosion of concrete structures, there can be required various properties such as absorption capacity and water permeability, adhesion and tensile strength, hair crack-resistance, impact-resistance, repeated low and high temperature test and chemical resistance, soundness for drinking water, soundness for drinking water and etc. In this study these engineering properties of composite systems using polymer-modified mortar and epoxy resins were examined and could be confirmed to satisfy the guidelines of KS. Especially, it was turn out that the adhesion properties was excellent and high crack-resistance up to 1.49 mm will be perform.

• 한국도로학회:학술대회논문집
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• 2010.09a
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• pp.347-350
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• 2010

• Corrosion Science and Technology
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• v.13 no.5
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• pp.178-185
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• 2014

Alloy 617 is considered as a candidate Ni-based superalloy for the intermediate heat exchanger (IHX) of a very high-temperature gas reactor (VHTR) because of its good creep strength and corrosion resistance at high temperatures. Helium is used as a coolant in a VHTR owing to its high thermal conductivity, inertness, and low neutron absorption. However, helium inevitably includes impurities that create an imbalance in the surface reactivity at the interface of the coolant and the exposed materials. As the Alloy 617 has been exposed to high temperatures at $950^{\circ}C$ in the impure helium environment of a VHTR, the degradation of material is accelerated and mechanical properties decreased. The high-temperature strength, creep, and corrosion properties of the structural material for an IHX are highly important to maintain the integrity in a harsh environment for a 60 year period. Therefore, an alloy superior to alloy 617 should be developed. In this study, the mechanical and high-temperature corrosion properties for Ni-Cr alloys fabricated in the laboratory were evaluated as a function of the grain boundary strengthening and alloying elements. The ductility increased and decreased by increasing the amount of Mo and Cr, respectively. Surface oxide was detached during the corrosion test, when Al was not added to alloy. However the alloy with Al showed improved oxide adhesive property without significant degradation and mechanical property. Aluminum seems to act as an anti-corrosive role in the Ni-based alloy.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.121-122
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• 2023

This study investigates the anti-corrosion properties of two eco-friendly pyridinium ionic liquids; 4DMN and 4DMP, in a 3.5% NaCl solution. Utilizing weight loss tests, EIS, PDP, quantum chemical calculations, and molecular dynamics simulations, the study demonstrates concentration-dependent inhibition efficiencies of 94% and 92% for 4DMN and 4DMP, respectively. The compounds modulate both anodic and cathodic reactions without altering the corrosion mechanism. EIS data suggest that a protective layer forms, supported by FE-SEM and AFM surface analyses, which reveal improved morphology and reduced roughness. Computational validations corroborate these empirical findings, highlighting the feasibility of these ionic liquids for effective, sustainable corrosion mitigation.

• Journal of the Korean Institute of Rural Architecture
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• v.12 no.4
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• pp.1-11
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• 2010

This study is a research examining reshaped pattern in the perspective of repairing parts and materials through repairing renovation of registered cultural properties constructed in modern times and results are as followings. Repairing construction of registered cultural properties of Jollanamdo according to parts is shown numerously in the order of roof, walls and windows, and mostly outworn as time passes on and leakage were the main cause of repair. Also when original shape was damaged by previous repair in the past, and this was another reason of repairing. It was surveyed that among the repairing job repair of damage occurred on the part of roofing area including water leakage, corrosion and damage of roofing material, and damage of groove channel were the most main cause of repair. Especially when roof leakage is occurred by outworn of roofing materials, this cause corrosion and damage of materials due to the damage of leakage parts and this cause repeating cycles of worse leakage again and again. Main repairing materials which deform the original shape of registered cultural properties were confirmed as copper plate used on the roof. Copper plate showing high frequency of application which replaces groove slate or cement roofing tile used on the roof before has high durability and anti-corrosion but it is considered improper material to recover original shape.