• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.77-77
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• 2010

We used eddy current sensor for diagnosis of power line. The power line according to the cross section has 6~18 element wires. The corrosion of power line was made by sodium hydroxide. The corrosion time of power line was from 18 hours to 27 hours. We obtained physical characteristics from tensile and torsion tests of power line. The eddy current Characteristics of power line according to the corrosion appeared change of amplitude 200 ~ 800 mV.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.252-255
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• 1996

Cl-based gas chemistry is generally used to etching for Al alloy metallization. After the etching of Al alloy with Cl-based gas plasma, residual chlorine on Al alloy reacts with $H_2O$ due to air exposure and results in Al corrosion. In this study, the corrosion Phenomena of Al were examined with XPS(X-ray photoelectron spectroscopy) and SEF(Scanning electron microscopy). It was confirmed that chlorine mainly existed at the grain boundary of Al alloy after plasma etching of Al alloy with Cl-based gas chemistry and Al corrosion was largely generated at the grain boundary of Al a1loy. And residual chlorine was passivated by sulfur and fluorine which were generated by SF$_{6}$ plasma. These effects of passivation reduced the Al corrosion due to air exposure.e.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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• pp.132-135
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• 2000

Direct current corrosion have being investigated by lots of scientists but Alternating current corrosion was ignored because the corrosion rate by AC was very small. Recently however, AC corrosion accidents have been reported in many other countries. So the study of AC corrosion is to be necessary in these days. In this paper, several experiments which intentionally imposed the AC or DC to the specimens also imposed AC and DC at the same time was carried out in the laboratory to examine the AC corrosion characteristics and in addition applied the same way in the field. Moreover, while the field investigations of the abnormal corrosion failures. It was the AC that caused one of corrosion failures.

• 한국정밀공학회지
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• 제26권8호
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• pp.47-54
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• 2009

In this study, a simple and effective method was proposed to minimize electrolytic corrosion on the workpiece during ED-drilling using water as a working fluid. The adhesion of a cover plate onto the surface of the workpiece was greatly effective for suppressing electrolytic corrosion during ED-drilling. The experiment revealed that the adhesion of the cover plate prevented corrosion without causing significant changes in machining characteristics. Using the machining method proposed in this paper, electrolytic-corrosion-free holes can be machined without change in the machinery system. By using corrosion-free hole as a start hole for wire EDM, a lead frame die with high quality was fabricated successfully.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2007년도 추계종합학술대회
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• pp.747-750
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• 2007

본 연구는 부식을 방지하기 위해서는 metal line식각 후 염소 잔유물 과 plasma charge up을 식각 조건, PR strip조건 및 후속 세정 조건을 최적화함으로써 제거해야 한다고 제안 하였다. Metal line에 다량 분포하는 charge up은 후속 세정의 적정 PH와 만났을 때, 하부 tungsten plug의 부식을 유발 하게 된다. Metal line식각 및 PR strip후 세정에 있어 약액의 종류는 부식에 결정적인 영향을 미친다. Galvanic corrosion을 최소화하기 위한 적정 PH, metal attack을 최소화 할 수 있는 chemistry선택, 높은 식각 부산물 제거 효율의 약액, 최적의 $H_2O$처리 조건 등이 metal부식방지에 있어 결정적인 요소임을 확인하였다.

• 한국표면공학회지
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• 제54권4호
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• pp.194-199
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• 2021

In this study, rebar corrosion detection sensor was fabricated using multi-walled carbon nanotubes (MWCNTs). MWCNTs were pre-treated in the acid electrolytes to attach the carboxylic acid to the surface of MWCNTs. The fabricated sensor was attached on the surface of rebar and it detected the corrosion of steel using LCR meter with variation of capacitance. The surface morphology and electrical properties were characterized using scanning electron microscope (SEM) and electrical test equipment, respectively. To verify the corrosion detection characteristics, comparison experiment using plastic bar was performed. Moreover, mechanism of corrosion detection sensor was discussed.

• Corrosion Science and Technology
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• 제21권6호
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• pp.487-494
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• 2022

Anodizing is a typical electrochemical surface treatment method that can improve the corrosion and insulating properties of aluminum alloys. The anodization process can obtain a dense structure. It can be used to artificially grow the thickness of an anodization film. Aluminum 3003 alloy used in this study is the most commonly used alloy for batteries due to its high strength and excellent formability as well as its weldability and corrosion resistance. Aluminum 3003 alloy was anodized at 0 ℃ with 0.3 M oxalic acid at 20 V, 40 V, or 60 V for 1 hour, 6 hours, or 12 hours. As a result of analyzing the composition of each specimen with an Energy Dispersive Spectrometer (EDS), aluminum was converted into an oxide film. The thickness of the formed anodization film increased when the applied voltage and anodization time increased. High corrosion potential values and low corrosion current density values were observed for the thickest oxide layer. The anodization film formed by anodization acted as a protective layer. The electrical resistance increased as the applied voltage and anodization time increased.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.339-342
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• 2003

The corrosion characteristics of Copper by oxidizers in Cu CMP slurry has been investigated. Key experimental variables that has been investigate are the corrosion rate by different oxidizers containing slurry of Cu CMP. Oxidizers in Cu CMP slurry reacts with Cu surfaces to raise the oxidation state of the metal via a reduction-oxidation reaction, resulting in either dissolution of the Cu or the formation of Ta surface film on the metal.[1] When Cu films were corroded adding each oxidizer, corrosion rate increased as much as higher Icorrosion. The corrosion rate of Cu was the largest as added $(NH_4)_2S_2O_8$. The higher content of Urea Hydrogen peroxide was, the higher corrosion rate was measured. Putting in tartaric acid as complexing agent, the corrosion rates of the compounds(Urea hydrogen peroxide+$H_2O_2$) are uniformly. As a result of Cu corrosion by $Cu(NO_3)_2$, the high corrosion rate was determined by even small amounts of $Cu(NO_3)_2$. Consequently, this can be explained by assuming that corrosion by oxidizers has primary effects on the removal rate of Cu and the proper oxidizer needs to be chosen in accordance with relationship of each slurry agent.

• 한국표면공학회지
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• 제54권6호
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• pp.294-301
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• 2021

As the number of cases of performance degradation owing to corrosion of plant during processing in industries increases, the cost of maintaining industrial factory is increasing year by the year. Most of the materials of the facilities are consist of stainless steel (SS) such as austenite SS, ferrite SS, martensite SS, and duplex SS. Among them austenite SS is cheap and has excellent corrosion resistance and heat resistance. Corrosion is the consumption and change of metals by altering chemical and electrical reactions. The types of SS corrosion include pitting corrosion, crevice corrosion, galvanic corrosion, stress corrosion cracking, and thermal corrosion. The corrosion of SS is not only investigated various environmental factors but also the measurement of the corrosion rate. Therefore, it aims to understand comprehensive corrosion rates in various environments using qualitative, quantitative and electrochemical methods.

• Corrosion Science and Technology
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• 제17권5호
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• pp.211-217
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• 2018

Natural degradation of grounding-electrode in soil environment should be monitored for several decades to predict the lifetime of the grounding electrode for efficient application and management. However, long-term studies for such electrodes have many practical limitations. The conventional accelerated corrosion test is unsuitable for such studies because simulated soil corrosion process cannot represent the actual soil environment. A preliminary experiment of accelerated corrosion test was conducted using existing test standards. The accelerated corrosion test that reflects the actual soil environment has been developed to evaluate corrosion performances of grounding-electrodes in a short period. Several test conditions with different chamber temperatures and salt spray were used to imitate actual field conditions based on ASTM B162, ASTM B117, and ISO 14993 standards. Accelerated degradation specimens of copper-bonded electrodes were made by the facile method and their corrosion performances were investigated. Their corrosion rates were calculated to $0.042{\mu}m/day$, $0.316{\mu}m/day$, and $0.11{\mu}m/day$, respectively. These results indicate that accelerated deterioration of grounding materials can be determined in a short period by using cyclic test condition with salt spray temperature of $50^{\circ}C$.