• Corrosion Science and Technology
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• 제13권1호
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• pp.15-19
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• 2014

Recently, anti-fouling paints which does not include the poison components such as tin(Sn), copper(Cu) have been increasingly developed in order to inhibit the environmental contamination of the sea water. Moreover, the wear ratios of these anti-fouling paints are very important problem to prolong their life time in economical point of view. In this study, five types of anti-fouling paints as self polishing type were investigated on the relationship between their polarization characteristics and wear ratios. It was verified that there was apparently a good relationship between the wear ratio and polarization characteristics, for example, the wear ratio increased with increasing the impedance ratio, and increased or decreased with the corrosion potential shifting in the negative or positive direction respectively. In addition, the wear ratio decreased with decreasing the corrosion current density. Consequently, it is suggested that we can qualitatively expect the wear ratio by only measuring the polarization characteristics. Therefore, before the examination of the wear ratio was actually carried out in the field, the evaluation of polarization property in the laboratory may give a available reference data for their developments.

• Korean Chemical Engineering Research
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• 제49권6호
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• pp.745-751
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• 2011

내부식성이 강화된 새로운 방청안료를 개발하기 위한 연구의 일환으로, 본 연구에서는 높은 내부식성을 제공하는 아연 및 세륨 이온 교환된 제올라이트를 도입하였다. 그리고 이온교환 제올라이트를 이용하여 프라이머 도료 제조 및 도장을 수행한 후, 그것의 방식성능을 측정하였다. 도장을 위한 금속 기재는 아연도금(galvanized, GI) 강판이었고, 도장된 강판의 방식성능은 electrochemical impedance spectroscopy(EIS)와 scanning vibrating electrode technique(SVET)으로 측정되었다. EIS 및 절단면의 내부식성을 확인하기 위한 SVET 측정으로부터 세륨이온 교환된 제올라이트가 가장 높은 효율을 제시하였고, 아연 및 세륨 이온 교환된 제올라이트의 경우 GI 강판에 대하여 cathodic 부식 방지제로 기여함을 확인할 수 있었다.

• Corrosion Science and Technology
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• 제18권6호
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• pp.228-231
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• 2019

Aluminum and its alloys have been widely used in various fields because of low weight, high strength, good conductivity, and low price. It is well known that aluminum alloys that cause natural oxide film can inhibit corrosion in wet, salty environments. However, these oxides are so thin that corrosion occurs in a variety of environments. To prevent this problem, an electrochemical anodizing technique was applied to the aluminum alloy surface to form a thick layer of oxide and a unique oxide shape, such as a hierarchical pore structure simultaneously combining large and small pores. The shape of the structures was implemented using stepwise anodization voltages such as 40 V for mild anodizing and 80 V for hard anodizing, respectively. To maximize water repellency, it is crucial to the role of surface structures shape. And a hydrophobic thin film was coated by 1H, 1H, 2H, 2H-Perfluorodecyltrichlorosilane (FDTS) to minimize surface energy of the structure surface. Thus, such nanoengineered superhydrophobic surface exhibited a high water contact angle and excellent corrosion resistance such as low corrosion current density and inhibition efficiency.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.359-364
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• 2001

The purpose of this study is to develop the repair system for RC members with damaged by rebar corrosion using new corrosion inhibitor which was high nitrite content. In the experiments, the acceleration corrosion test of rebar was conducted using the specimen which was applied by various repair system. As a result, it was confirmed that the new repair system without concrete patching had high anti-corrosion property compared with other repair systems and was very effective as a spray type corrosion inhibitor in concrete containing chloride (0.1% of NaCl).

• 동력기계공학회지
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• 제18권2호
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• pp.37-42
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• 2014

The purpose of this paper is to investigate polarization characteristics of heat-treated Ni-based self-flux alloy coating in alkaline solution. Ni-based self-flux alloy powder was sprayed to a steel substrate using flame spray process, and heat treatments were performed in a vacuum furnace at $800^{\circ}C$, $900^{\circ}C$, $1000^{\circ}C$ and $1100^{\circ}C$. After heat treatments, corrosion tests were carried out using potentiostat/galvanostat at solution with pH 8 and pH 13. Corrosion potential(Ecorr) and corrosion current density(Icorr) could be analyzed from polarization curve. Anticorrosive effect of heat-treated coating at solution with pH 8 was relatively greater than at solution with pH 13. Heat-treated coating at $1100^{\circ}C$ showed the greatest anti-corrosion characteristics in alkaline solution.

• Corrosion Science and Technology
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• 제10권6호
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• pp.205-211
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• 2011

The severe corrosion environment makes the steel product lifecycle short while Cu-alloys with anti-corrosion characteristic used in sea water are too expensive. This study shows that the Cu-alloy(Cu-37.25% Zn-0.67%Al) used in sea water environment can be superseded by SS400 with various coating process, evaluating electrochemical characteristics. Three coating processes were applied to SS400 such as PTFE + Zn coaing, Zn + PTFE coating and only Zn electrogalvanizing coaing. Various electrochemical experiments such as open circuit potential measurments, potentiodynamic polarization tests and analyses of Tafel constants. Mechanical properties were also measured by tensile test and hardness tests. As a result, Zn + PTFE coating for SS400 steel presented the excellent anti-corrosion characteristic in sea water.

• 공업화학
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• 제32권6호
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• pp.653-658
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• 2021

Polyvinylidene fluoride (PVDF)는 우수한 가공성을 가지고 있어 코팅 재료로 유망하지만 다른 불소계 고분자에 비하여 소수성이 약하여 부식 방지 등 그 응용에 제한이 있다. 본 연구에서는 PVDF의 부식방지 특성을 향상시키고자 사불화탄소(CF₄) 가스를 이용하여 플라즈마 불소화를 수행하였고, 유량에 따른 불소 함량 및 소수성 변화를 고찰하고 부식방지 특성을 확인하였다. PVDF 막 표면의 불소 함량은 사불화탄소 유량이 증가함에 따라 46.70%로 증가하였으나 그 표면자유에너지는 불소함량의 증가와 일치하지 않았다. 한편, PVDF 표면의 표면 거칠기는 불소화 유량에 따라 최대 150% 증가하다가 다시 감소하는 경향을 보였다. 이는 플라즈마 불소화는 불소화 기능기 도입 및 표면식각으로 인하여 표면자유에너지에 영향을 주는 것으로 판단된다. 또한, PVDF 코팅된 철판의 부식 정도는 미처리 철판에 비하여 표면 산소 함량이 49.2%에서 19.0% 이하로 크게 개선되었으며, 특히, 불소화 처리된 PVDF의 산소함량은 13.6%으로 불소화 처리되지 않은 PVDF보다 28.4 % 정도 낮아져 우수한 부식방지 특성을 보이는 것으로 관찰되었다.

• 공업화학
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• 제22권4호
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• pp.367-375
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• 2011

숙신산 에스테르 유도체는 방청성능 및 윤활성능이 우수하여 금속가공유 및 유압작동유 등의 첨가제로 많이 사용되고 있다. 본 연구에서는 광유계 윤활기유의 방청제로 사용하기 위하여 알킬 무수 숙신산과 여러 가지 지방 알콜과의 개환반응을 행하여 카르복실 그룹과 에스테르 그룹을 동시에 함유하는 숙신산 알킬 하프-에스테르 유도체를 97% 이상의 수율로 합성하였으며 1 중량% 농도범위에서 광유계 오일에 잘 용해되었다. 합성 유도체는 $^1H-NMR$ 및 FT-IR 스펙트럼으로 구조를 확인하였으며, GC 분석을 통하여 화합물의 순도를 확인하였다. 또한, 합성 유도체의 해수에 대한 방청성능을 ASTM D665 표준방법과 무게 중량법으로 평가하여 카르복실산 그룹을 함유하지 않는 숙신산 알킬 에스테르 유도체와 비교하였다. 방청성능 평가 결과, 합성 유도체의 농도가 증가하고 분자 내에 포함된 알킬기의 사슬이 짧을수록 상대적으로 방청성능이 우수하였으며 비교물질인 숙신산 알킬 에스테르 유도체는 방청성능을 전혀 나타내지 않았다. 무게 중량법으로 평가한 80 중량ppm 농도를 첨가한 오일의 방청효율 % (IE%)는 알킬기의 사슬이 짧을수록 높은 값을 나타내어 최고 95% 이상이었다. 또한, 발청속도(Corrosion rate, CR)는 알킬기의 사슬이 짧을수록 낮은 값을 나타내어 80 중량ppm에서 최고 0.3 mm/year 이하를 나타내었다. 즉, 숙신산 알킬 하프-에스테르 유도체의 해수에 대한 방청성능은 분자 내에 함유되어 있는 카르복실산 그룹으로 인하여 나타나는 것으로 판단되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.137-138
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• 2017

The Waterproofing and Anti corrosion materials applied to the water supply facility did not consider environment of water supply facility, thus defects occurred consistently on the site. In this study, it suggests safety adhesion test of wet surface and have a test for safety adhesion performance.

• 한국표면공학회지
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• 제26권6호
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• pp.307-315
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• 1993

A study on a new anti-finger printed EGI steel sheet with high corrosion resistance has been carried out to meet the recent requirement of high quality and performance of the pure zinc electrogalvanized steel sheet. The substrate was the pure zinc electrogalvanized sheet with the metallic coating of 20g/$\m^2$. The two differ-ent processes for inorganic(chromating) and organic(resin) coating were applied. One was a two coat/two bake type to separately treat chromating and resin coating which is now widely used. The other was a one coat/one bake type to simultaneously treat them which is newly developed in this study. The solution for the one coat/one bake type was an aqua-base coating agents which was composed of inorganic and organic components. The new anti-finger printed EGI steel sheet with the Cr and resin coating weight of 13mg/$\m^2$ and 800mg/$\m^2$, respectively shows the superior corrosion resistance besides the good paintability, formability fingerprint resistance and earth characteristics properties.