Semiconductivity of steam generator tubing alloys in simulated crevice chemistries containing lead and sulphur

Xia, Da-Hai; Behnamian, Yashar; Yang, Lixia; Fan, Hongzhen; Zhu, Renkang; Luo, Jing‐Li; Lu, Yucheng; Klimas, Stan J.

doi:10.1179/1743278215y.0000000031

Cited by 30 publications

(8 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5,10 Some impurities including SO 4 2− and Cl − in the secondary loop water can concentrate within these crevices. 11,12 In order to avoid elevated corrosion potential of SG alloy and minimize oxygen content, hydrazine is intentionally added to the secondary loop of SGs, leading to a reduction of sulfate to HS − , H 2 15 which have been recognized to enhance active dissolution of metal, increase stress corrosion cracking and pitting susceptibility. [15][16][17] As pointed out by Newman, 2 some corrosion phenomena in SG tubing with the presence of 'reduced' sulfur species and oxygen have been recognized to occur at low temperature.…”

mentioning

confidence: 99%

Factors Influencing Passivity Breakdown on UNS N08800 in Neutral Chloride and Thiosulfate Solutions

Wang

Shi

et al. 2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

In this work, the passivity degradation of UNS N08800 in solutions containing Cl − and S 2 O 3 2− is studied by using polarization curve, electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS). Experimental results reveal that the passivity breakdown heavily depends on anodic potentials, concentration ratios of Cl − to S 2 O 3 2− , and the composition of materials. A combined effect between Cl − and S 2 O 3 2− on pitting corrosion is observed at high anodic potentials at which the passive film is broken down; in this situation, S 2 O 3 2− ions can enter into the pits by electromigration, and they are reduced to S ads and S 2− , stabilizing the metastable pits and accelerate the pit growth rate. However, there is no such combined effect at low anodic potentials when the passive film is intact, on the contrary, S 2 O 3 2− is beneficial to passivity in chloride solutions. At low anodic potentials, the interaction of S 2 O 3 2− with an intact passive layer is weak, and the adsorption of S 2 O 3 2− would mitigate the detrimental effect of Cl − ions.

show abstract

mentioning

confidence: 99%

Factors Influencing Passivity Breakdown on UNS N08800 in Neutral Chloride and Thiosulfate Solutions

Wang

Shi

et al. 2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…The donor concentration (N D ) of the passive film was calculated using the M-S equation: where S is the slope of the Mott-Schottky plot, e is the electronic charge (1.602 Â 10 À19 C), « 0 is the permittivity of free space (8.854 Â 10 À12 F•m À1 ) and « r is the relative permittivity (Xia et al, 2016). When assuming iron oxide as the steel surface passive film, the relative permittivity is 12.…”

Section: Mott-schottky Analysismentioning

confidence: 99%

Effect of chloride concentration on the properties of passive film formed on Q235 steel in simulated concrete pore solutions

Liu

Gao

et al. 2022

ACMM

View full text Add to dashboard Cite

Purpose This paper aims to study the effect of chloride concentration on the properties of passive film formed on Q235 steel in simulated concrete pore solutions. Design/methodology/approach Mott–Schottky analysis and electrochemical impedance spectroscopy were used to study the passive film of Q235 steel in simulated concrete pore solution. X-ray photoelectron spectroscopy was used to analyze the composition of passive film on Q235 steel. Findings When the chloride concentration is below the chloride threshold value, open circuit potential (OCP) and Rct gradually increases and donor concentration (ND) remains unchanged with the increasing immersion time. When the chloride concentration exceeds chloride threshold value, OCP and Rct decreases after a temporary increase and ND increases. The linear region of the Mott–Schottky curve lost its linearity. The electrochemical process control step is changed from charge transfer control to oxygen diffusion control. As the chloride concentration increases, the FeO content in the passive film increases and the Fe2O3 content decreases. Chloride can destroy the outer layer of passive film and introduce impurities. Originality/value The effects of chloride and immersion time on the change process of passive films on Q235 steel in simulated concrete pore solution were studied using electrochemical methods. The mechanism of chloride destroying passive film was analyzed.

show abstract

“…The change in film thickness was attributed to an increase in the activation energy of the outer layer on the specimen surface at high temperature [36]. The temperature had significant influence on the composition, structure and thickness of passive film or corrosion product film formed on the Ni-base alloys [37,38]. For instance, Huang et al [39] investigated the electrochemical properties and growth mechanism of passive films on Alloy 690 in solutions in the temperatures ranging from 20 to 300°C.…”

Section: Secondary Ion Mass Spectrometrymentioning

confidence: 99%

Passivation degradation of Alloy 800 on nucleate boiling surface

Xia

Zhou

Wang

et al. 2017

Corrosion Engineering, Science and Technology

View full text Add to dashboard Cite

In this work, the passivation degradation of Alloy 800 on nucleate boiling surface was studied by using polarisation curve, electrochemical impedance spectroscopy and secondary ion mass spectrometry. Experimental results indicated that boiling bubble would significantly degrade the passive film, as indicated by a decreased pitting potential and increased passive current density. Under boiling condition, the mass transfer of electrolyte is accelerated and the temperature of Alloy 800 was increased, as a result, the cathodic reaction and the dissolution rate of the passive film were increased. The passive film was Cr-depleted but Ni-and Fe-enriched, and the decreased Cr content in the passive film led to a degraded passive film.

show abstract

Semiconductivity of steam generator tubing alloys in simulated crevice chemistries containing lead and sulphur

Cited by 30 publications

References 64 publications

Factors Influencing Passivity Breakdown on UNS N08800 in Neutral Chloride and Thiosulfate Solutions

Factors Influencing Passivity Breakdown on UNS N08800 in Neutral Chloride and Thiosulfate Solutions

Effect of chloride concentration on the properties of passive film formed on Q235 steel in simulated concrete pore solutions

Passivation degradation of Alloy 800 on nucleate boiling surface

Contact Info

Product

Resources

About