• Corrosion Science and Technology
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• v.4 no.5
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• pp.178-190
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• 2005

In order to develop a new corrosion sensor for detecting and monitoring the external and internal corrosion damage of buried pipeline, the electrochemical property of sensors and the correlation of its output to corrosion rate of steel pipe, were evaluated by electrochemical methods in two soils of varying resistivity (5,000 ohm-cm, 10,000 ohm-cm) and synthetic tap water environments. In this paper, two types of galvanic probes were manufactured: copper-pipeline steel (Cu-CS) and stainless steel-pipeline steel (SS-CS). The corrosion behavior in synthetic groundwater and synthetic tap water for the different electrodes was investigated by potentiodynamic test. The comparison of the sensor output and corrosion rates revealed that a linear relationship was found between the probe current and the corrosion rates. In the soil resistivity of $5,000{\Omega}-cm$ and tap water environments, only the Cu-CS probe had a good linear quantitative relationship between the sensor output current and the corrosion rate of pipeline steel. In the case of $10,000{\Omega}-cm$, although the SS-CS probe showed a better linear correlation than that of Cu-CS probe, the Cu-CS probe is more suitable than SS-CS probe due to the high current output.

• Journal of environmental and Sanitary engineering
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• v.7 no.1
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• pp.1-16
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• 1992

Corrosion of pipes Is one of the most serious problems in the maintenance of water worlds. Corrosion is promoted not only by physical factors such as temperature, but also by electrochemical factors including concentration of soluble metal ions, chlorine ion, pH, DO and microorganisms. Corrosion products also affect corrosion rate. In this research, study results are summarized as follows ; 1) Corrosion test was performed for 4 weeks at $70^{\circ}C$, pH 7.0 with specimens of 4 types of metal materials used as service pipes. Corrosion rate and S.E.M were analyzed. The results were showed that corrosion 1.ate of carbon steel pipe was 4.10~5.22 $mg/\textrm{cm}^2$ . week, galvanized steel pipe 0.98~1.34$mg/\textrm{cm}^2$. week, Copper pipe 0.02~0.04$mg/\textrm{cm}^2$. week, stainless steel pipe 0.05~ 0.10$mg/\textrm{cm}^2$ . week. 2) When corrosion rate was tested for tile types of pipes at pH 7 and both $25^{\circ}C$ and $75^{\circ}C$, avaerage corrosion rate for 6 weeks at $25^{\circ}C$ Ivas 2.26$mg/\textrm{cm}^2$ . week in carbon steel pipe, 1.99$mg/\textrm{cm}^2$. week in galvanized steel pipe, 0.26 $mg/\textrm{cm}^2$. week in stainless steel pipe. At $87^{\circ}C$, average corrosion rate for 4 weeks u.3s 4.56 $mg/\textrm{cm}^2$. week in carbon steel pipe,

• Journal of Ocean Engineering and Technology
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• v.2 no.2
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• pp.78-86
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• 1988

In order to investigate the corrosion pit occurrence and growth characteristic of M.E.F.(martensite encapsulated islands of ferrite) dual phase steel was made with a suitable heat treatment of raw material(SS41), a corrosion fatigue test was performed under rotary bending in the salt solution having a concentration from 0.01 wt percent to 3.5 wt percent. The fatigue strength of dual phase steel was remarkably decreased with an increase in concentration of salt solution; approximately from 63% to 80% in case of dual phase steel and from 40% to 71% in case of raw material. Corrosion pit occurred in the martensite phase and fatigue cracks from corrosion pits were selectively propagated in martensite phases. In the observation of corrosion pits at the origin of fatigue cracks, it had been found that corrosion pits were grown into hemispherical pits and a/c(the surface diameter, 2c and the depth, a of corrosion pit)was about 1.0-1.5regardless of the variation of salt solution concentration. The difference of corrosion pit depth growth rate was increased with an increase in concentration of salt solution according to an increase in stress level.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.769-775
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• 2017

The corrosion behavior of stainless steel (304 and 316 type) and copper induced by LiCl-KCl at low temperatures in the presence of sufficient oxygen and moisture was investigated through a series of experiments (at $30^{\circ}C$, $40^{\circ}C$, $60^{\circ}C$, and $80^{\circ}C$ for 24 hours, 48 hours, 72 hours, and 96 hours). The specimens not coated on one side with an aqueous solution saturated with LiCl-KCl experienced no corrosion at any temperature, not even when the test duration exceeded 96 hours. Stainless steel exposed to LiCl-KCl experienced almost no corrosion below $40^{\circ}C$, but pitting corrosion was observed at temperatures above $60^{\circ}C$. As the duration of the experiment was increased, the rate of corrosion accelerated in proportion to the temperature. The 316 type stainless steel exhibited better corrosion resistance than did the 304 type. In the case of copper, the rate of corrosion accelerated in proportion to the duration and temperature but, unlike the case of stainless steel, the corrosion was more general. As a result, the extent of copper corrosion was about three times that of stainless steel.

• Corrosion Science and Technology
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• v.22 no.3
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• pp.137-152
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• 2023

Polarization behavior and corrosion inhibition of copper in acidic chloride solutions containing benzotriazole were studied. Pourbaix diagrams constructed for copper in NaCl solutions with different BTAH concentrations were used to understand the polarization behavior. Open circuit potential (OCP) depended not only on chloride concentration, but also on whether a CuBTA layer was formed on the copper surface. Only when the (pH, OCP) was located well in the CuBTA region of the Pourbaix diagram, a stable corrosion inhibiting CuBTA layer was formed, which was confirmed by X-ray Photoelectron Spectroscopy (XPS) and a long-term corrosion test. The OCP for the CuBTA layer decreased logarithmically with increasing [Cl^-] activity in the solution. A minimum BTAH concentration required to form a CuBTA layer for a given NaCl concentration and pH were determined from the Pourbaix diagram. It was found that 320 ppm BTAH solution could be used to form a corrosion-inhibiting CuBTA layer inside the corrosion pit in the sprinkler copper tube, successfully reducing water leakage rate of copper tubes. These experimental results could be used to estimate water chemistry inside a corrosion pit.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.284-289
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• 2004

The present paper describes an experimental study on the corrosive behaviour of Rolling stock structures. It is important to predict corrosive behaviour of rolling stock structures for safe service and to know relation between corrosion and fatigue life. This paper practiced electrochemical corrosion test of SS400 and SM490A. This study will examine the corrosive properties and differences of SS400 and SM490A from measuring corrosion potential and corrosion current density.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.718-723
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• 2000

Corrosion is a world wide problem effecting a large number of structure. Cost of repair and rehabilitation on reinforcement structure damaged by steel corrosion is expensive. But structural capacity on low level corrosion is increased. So this experimental study was performed to know structural performance on reinforced concrete slabs with low level corroded bars. As in the case of test samples, bond stress and structural capacity increases up to 2% corrosion level.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.135-139
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• 2002

Most of all the mechanical devices are becoming more high-speed and high-power as well as their used condition being more polluted. So, it is necessary for these devices to equip cooling system to overcome that kind of severe using condition. In this study, corrosion test was carried out in distilled and tap water for the investigation on the corrosion characteristics of Al-alloy that is using as material for radiator.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.941-948
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• 2024

The effects of radiation on the corrosion of canister materials were investigated for the reliable disposal of high-level radioactive waste. The test specimens were gamma-irradiated at a very low dose rate of approximately 0.1 Gy/h for six and twelve months. The copper and cast iron species were less corroded when irradiated. It is hypothesized that gamma rays suppress the formation of lower-enthalpy species like metal oxides and activate reductive reactions. In contrast, it was difficult to evaluate the effect of radiation on the corrosion of titanium and stainless steel.

• 보존과학연구
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• s.7
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• pp.292-303
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• 1986

The purpose of this paper is to select the suitable resin as changed in environmental and ingredients, in the conservation of metallic objects. Disposal way of metallic objects were used to various resin and grease which will must be well selected in the nature of relics. The contents of this report are summed up as follows ; The resins of Incralac, Ruscoat, wash primer, Amerlock-400 wrer coated on the slice of ironware (5% saltspray test on the view of nature & Adherence). After the coating, add increasing speed to a corrosion rate, and then the adherence of resins were tested. In this study corrosion test, 0.10-0.25% Amerlock-400 jis proved to be a rare one of corrosion rate and 1.0-2.5% Wash primer is found to be a plenty one of corrosion area.