• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.835-841
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• 2011

Corrosion inhibition of mild steel by nevirapine, an antiretroviral has been investigated using potentiodynamic polarization, electrochemical impedance spectroscopy technique and weight loss methods. The experimental results suggested, nevirapine is a good corrosion inhibitor for mild steel in 1M hydrochloric acid medium and the inhibition efficiency increased with increase in inhibitor concentration. The kinetic parameters for corrosion process and thermodynamic parameters for adsorption process were calculated and discussed. The adsorption of the inhibitor on the surface of mild steel followed Langmuir adsorption isotherm.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.125.1-125.1
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• 2016

마그네슘 합금은 소재 특성상 표면처리가 필수불가결하다. 금속의 다양한 표면처리 방법 중 마그네슘 합금은 크게 화학적 반응을 이용해 산화막을 생성해 피막을 올리는 화성처리법과, 전해액 내에 침지시켜 전기를 걸어주어 금속 표면에 플라즈마 아크를 통해 산화막을 생성하는 PEO공법 두 가지 방법이 있다. 본 연구에서는 마그네슘 합금 소재에 PEO공법을 적용한 산화피막의 공정 변수에 따른 특성을 SEM, EDS, SST, potentiodynamic polarization 등으로 분석하였다.

• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.134-139
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• 1999

In this study, PSII(plasma source ion implantation) was used to improve the biocompatibility of bone-anchored Ti implant. According to potentiodynamic anodic polarization test in deaerated Hank's solution, open circuit potential of ion implanted specimens were increased compare to that of unimplanted specimen ; besides, passive current density and critical anodic current density of ion implanted specimens were lower than unimplanted specimen.

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.28-28
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• 2002

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.244-245
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• 2009

Sol-gel coatings of $TiO_2$ have been prepared from $TiO_2$ sol and deposited by dip-coating technique on 316L stainless steel sheets in order to study the electrochemical behaviorin corrosive solutions. The influence of the coatings on the chemical corrosion of the substrate has been evaluated by potentiodynamic polarization curves in different aqueous NaCl solution at $25^{\circ}C$.

• Corrosion Science and Technology
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• v.8 no.1
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• pp.1-10
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• 2009

The influence of Schiff bases on the corrosion inhibition of mild steel in 1 M $H_2SO_4$ have been investigated by weight loss, gasometry, impedance and polarization techniques. The results obtained reveal that these compounds act as good inhibitors. The inhibition efficiency of Schiff bases increased with concentration and synergistically increased on addition of chromate, sulphate and halide ions. Potentiodynamic polarization measurements clearly reveal that the investigated inhibitors are of mixed type but they are more cathodic in nature. The adsorption of these compounds on mild steel surface for both the acids were found to obey Langmuir adsorption isotherm. The surface morphology was studied by SEM and UV reflectance spectra.

• Journal of the Korean Chemical Society
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• v.58 no.2
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• pp.160-168
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• 2014

The electrochemical behavior and corrosion inhibition of zinc in 0.5 M $H_2SO_4$ in the absence and presence of some chromones has been investigated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. The presence of these investigated compounds in the corrosive solutions decrease the weight loss, the corrosion current density, and double layer capacitance but increases the charge transfer resistance. Polarization studies were carried out at room temperature, and showed that all the studied compounds act as mixed type inhibitors with a slight predominance of cathodic character. The effect of temperature on corrosion inhibition has been studied and the thermodynamic activation and adsorption parameters were determined and discussed. The adsorption of the investigated compounds on zinc was found to obey Langmuir adsorption isotherm.

• Corrosion Science and Technology
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• v.5 no.2
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• pp.62-68
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• 2006

Solvent free high solid coatings are increasingly used as they posses number of advantages such as, lower cost per unit film thickness, better performance and eco-friendliness. In the present study polymeric film-forming materials such as aniline-novolac (ANS), cresol-novolac (CNS) and acrylic copolymer blended cresol-novolac (ACNS) coating materials have been prepared. The corrosion resistance properties of the prepared high solid coating materials have been evaluated through potential-time, potentiodynamic polarization and electrochemical impedance studies (EIS). Among the three coating systems, cresol-novolac polymer coated substrates offer better corrosion resistance property and the order of the performance was found as CNS > ACNS > ANS. We can recommend these systems for use in automobile applications.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1281-1284
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• 2005

In the micro electrochemical machining (ECM), unfavorable oxide/passive layer formation and overall corrosion of electrodes must be prevented. Generally, the stainless steel electrode corrodes, passivates or dissolves in the electrochemical cell according to the electrode potential. Therefore, the electrode must maintain stable potential. The stable electrode potentials of tool and workpiece were determined with the potentiodynamic polarization test and verified experimentally from the point of machining stability and machined surface quality.

• Journal of Welding and Joining
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• v.4 no.3
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• pp.58-71
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• 1986

Mechanical and corrosion property of duplex stainless steel weldments made by the GTAW and SMAW process were studied. Fracture toughness, general and local corrosion resistance of GTAW and SMAW weldments were evaluated in terms of Charpy V notch impact test, anodic polarization diagram, pitting corrosion rate, respectively. SMA weld metal showed much lower impact toughness and higher ductile-brittle transition temperature than GTA weld metal. Fractographic and EDX analysis on fracture surface of SMA weld metal demonstrated the existence of (Si, Ti), oxide in large amounts. Potentiodynamic anodic polarization diagram of GMA weld metal showed much lower passive current density than SMA weld metal in 4% $H_2/SO_4$ solution. And pitting corrosion rate test showed the same tendency. Relating the microstructure, chemistry and property, it can be concluded that GTA weld metal gives better toughness due to lower oxygen content, i.e. lower inclusion content, and better corrosion resistance due to higher Pitting Index(PI) than SMA weld metal.