scholarly journals Stochastic Modeling of the Influence of Environment on Pitting Corrosion Damage of Radioactive-Waste Containers

1994 ◽  
Vol 353 ◽  
Author(s):  
Gregory A. Henshall
Keyword(s):  
Radioactive Waste ◽  
Pitting Corrosion ◽  
Chloride Ion ◽  
Corrosion Damage ◽  
Absolute Temperature ◽  
Ion Concentration ◽  
Stochastic Parameters ◽  
Physically Based ◽  
High Level ◽  
Pit Initiation

AbstractA physically-based, phenomenological stochastic model for pit initiation and growth is presented as a potential tool for predicting the degradation of high-level radioactive-waste containers by aqueous pitting corrosion. Included in the model are simple phenomenological equations describing the dependence of the controlling stochastic parameters on the applied (or corrosion) potential, chloride ion concentration, and absolute temperature. Results from this model are presented that demonstrate its ability to simulate several important environmental effects on pitting.

Exploration of the effect of chloride ion concentration and temperature on pitting corrosion of carbon steel in saturated Ca(OH) 2 solution

2015 ◽  
Vol 98 ◽  
pp. 708-715 ◽  
Author(s):  
Samin Sharifi-Asl ◽  
Feixiong Mao ◽  
Pin Lu ◽  
Bruno Kursten ◽  
Digby D. Macdonald
Keyword(s):  
Carbon Steel ◽  
Pitting Corrosion ◽  
Chloride Ion ◽  
Ion Concentration

Simulation Investigation on Environment-Induced Pitting Corrosion on the Metal Surface

2021 ◽  
Vol 13 (5) ◽  
pp. 820-828
Author(s):  
Wei Zhang ◽  
Shengli Lv ◽  
Leijiang Yao ◽  
Xiaoyan Tong
Keyword(s):  
Mathematical Model ◽  
Pitting Corrosion ◽  
Three Dimensional ◽  
Corrosion Damage ◽  
Sudden Onset ◽  
Ion Concentration ◽  
Two Dimensional Image ◽  
Aging Aircraft ◽  
Efficient Calculation ◽  
The Mathematical Model

The prediction of corrosion damage is one of effective research methods in the safety inspection of aging aircraft structures. A mathematical model for quantifying corrosion damage is used in this paper to predict the onset of corrosion on structural surfaces exposed to aggressive environments. Based on the finite difference technique, the evolution process of local pitting corrosion on the surface of aluminum alloy in the medium is simulated, which can consider the sudden onset and the randomness of pitting corrosion. The effect of local ion concentration and oxide film damage on subsequent pitting nucleation was analyzed. Based on the efficient calculation program, the effectiveness of the mathematical model is verified by the comparison between the corrosion damage morphology and the experimental data in the literature. The results show a more widespread distribution of subsequent pits because of stronger aggressive ions are released during the life cycle of active pits and the higher diffusion coefficient of the aggressive ions. The three dimensional morphology is generated by image processing method based on the gray value of the two dimensional image of pits.

scholarly journals Studies on Pitting Corrosion of Al-Cu-Li Alloys Part II: Breakdown Potential and Pit Initiation

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1786 ◽  
Author(s):  
Elmira Ghanbari ◽  
Alireza Saatchi ◽  
Xiaowei Lei ◽  
Digby D. Macdonald
Keyword(s):  
Barrier Layer ◽  
Pitting Corrosion ◽  
Mean Diffusivity ◽  
Corrosion Damage ◽  
Critical Parameters ◽  
Breakdown Potential ◽  
Linear Relationships ◽  
Aluminum Lithium ◽  
Ph Optimization ◽  
Pit Initiation

Prediction of the accumulated pitting corrosion damage in aluminum-lithium (Al-Li) is of great importance due to the wide application of these alloys in the aerospace industry. The Point Defect Model (PDM) is arguably one of the most well-developed techniques for evaluating the electrochemical behavior of passive metals. In this paper, the passivity breakdown and pitting corrosion performance of AA 2098-T851 was investigated using the PDM with the potentiodynamic polarization (PDP) technique in NaCl solutions at different scan rates, Cl− concentrations and pH. Both the PDM predictions and experiments reveal linear relationships between the critical breakdown potential (Ec) of the alloy and various independent variables, such as a C l − and pH. Optimization of the PDM of the near-normally distributed Ec as measured in at least 20 replicate experiments under each set of conditions, allowing for the estimation of some of the critical parameters on barrier layer generation and dissolution, such as the critical areal concentration of condensed cation vacancies (ξ) at the metal/barrier layer interface and the mean diffusivity of the cation vacancy in the barrier layer (D). With these values obtained—using PDM optimization—in one set of conditions, the Ec distribution can be predicted for any other set of conditions (combinations of a Cl − , pH and T). The PDM predictions and experimental observations in this work are in close agreement.

Corrosion of Stainless Steel for HLW Containers Under Gamma Irradiation

1992 ◽  
Vol 294 ◽  
Author(s):  
K. Osada ◽  
S. Muraoka
Keyword(s):  
Stainless Steel ◽  
Radioactive Waste ◽  
Gamma Irradiation ◽  
Pitting Corrosion ◽  
Electrochemical Method ◽  
Fission Products ◽  
304 Stainless Steel ◽  
Redox Potentials ◽  
High Level Radioactive Waste ◽  
High Level

ABSTRACTThe corrosion behavior of type 304 stainless steel was studied under gamma irradiation as part of the evaluation for the long-term durability of high-level radioactive waste (HLW) disposal containers. Gamma rays, generated from fission products in high-level radioactive waste, are considered to change the environment around the canisters and overpacks. The redox potentials for NaCl solutions and corrosion potentials of stainless steel were measured to consider the effects of gamma irradiation, by using an electrochemical method. The pitting potentials of stainless steel for NaCl solutions were also measured to examine the pitting corrosion under gamma irradiation. As a result of this experiment, it is concluded that the oxidizing properties as a result of the formation of H2O2 and H2 produced by gamma irradiation depended on the concentration of Cl−, and that the strength of oxidizing properties of 1M (mol·dm−3) NaCl solution was particularly high. and the pitting corrosion was found for 1M NaCI solution under gamma irradiation at the dose rate of 2.6×102 C/kg·h (1.0×106 R/h) at 60°C, by using an electrochemical method.

Effect of Inclusion on Pitting Corrosion of X80 Pipeline Steel

2015 ◽  
Vol 1120-1121 ◽  
pp. 999-1002 ◽  
Author(s):  
Feng Jun Lang ◽  
Xian Qiu Huang ◽  
Tao Pang ◽  
Ying Ma ◽  
Peng Cheng ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Pitting Corrosion ◽  
Corrosion Potential ◽  
Pipeline Steel ◽  
Chloride Ion ◽  
Steel Sample ◽  
Ion Concentration ◽  
Electrochemical Test ◽  
X80 Pipeline Steel ◽  
Atomic Force

The influence of inclusion on pitting corrosion of X80 pipeline steel was investigated by using electrochemical test and atomic force microscope. The results indicated that corrosion potential of X80 pipeline steel sample with higher grade inclusion was lower, and decreased significantly with chloride ion concentration increasing. Inclusion was not conducive to corrosion resistance of X80 pipeline steel. The way of X80 pipeline steel pitting corrosion was that pit formed at the inclusion dissolution, and grew to pitting. There were less corrosion products near the pit hole, forming a cathode ring.

scholarly journals CO2 Corrosion of Carbon Steel: The Synergy of Chloride Ion Concentration and Temperature on Metal Penetration

CORROSION ◽  
10.5006/3583 ◽  
2020 ◽  
Vol 76 (11) ◽  
Author(s):  
Frederick Pessu ◽  
Richard Barker ◽  
Anne Neville
Keyword(s):  
Carbon Steel ◽  
Pitting Corrosion ◽  
Synergistic Effects ◽  
Chloride Concentration ◽  
Chloride Ion ◽  
Corrosion Products ◽  
Ion Concentration ◽  
Co2 Corrosion ◽  
Passive Alloys ◽  
C 50

This paper investigates the synergy of chloride ion concentration and temperature on the general and pitting corrosion of carbon steel in CO2-saturated environments. Experiments were conducted over 168 h in different concentrations of NaCl brines (1 wt%, 3.5 wt%, and 10 wt%) and temperatures (30°C, 50°C, and 80°C) with the aim of elucidating the combined effect of changes in chloride ion concentration and temperature on overall metal degradation, taking into consideration general and pitting corrosion. This also includes a correlation with the formation and properties of FeCO3 corrosion products. Linear polarization resistance was implemented to monitor the electrochemical responses. Corrosion product characteristics and morphologies were studied through a combination of scanning electron microscopy and x-ray diffraction. Pitting corrosion evaluation was conducted through the application of 3D surface profilometry to study pit geometries such as the depth and diameter. The results show that general and pitting corrosion are strongly correlated to the synergistic effects of changing chloride ion concentration and temperature in carbon steel as a result of their combined influence on ferrite (Fe) dissolution and FeCO3 formation. This represents a paradigm shift from the already established mechanisms on chloride ion and temperature effects on passive alloys such as stainless steel. Increasing chloride ion concentration and temperature up to 10 wt% NaCl and 50°C to 80°C, respectively, is observed to increase the rate of Fe dissolution and formation of semiprotective FeCO3 corrosion products, leading to the increased manifestation and severity of pitting corrosion. The results also show that a “threshold chloride concentration” exists at 30°C, above which there is no significant increase in corrosion rate. However, such “threshold effects” were not observed at higher temperatures evaluated in the range of chloride concentration considered in this study.

An Electrochemical Study Of Pitting Corrosion in Stainless Steels (Part 1—Pit Growth)

CORROSION ◽  
1959 ◽  
Vol 15 (1) ◽  
pp. 48-54 ◽  
Author(s):  
N. D. GREENE ◽  
M. G. FONTANA
Keyword(s):  
Stainless Steel ◽  
Pitting Corrosion ◽  
Stainless Steels ◽  
Chloride Ion ◽  
Corrosion Current ◽  
Ion Concentration ◽  
Solution Composition ◽  
Current Interruption ◽  
Percent Nickel ◽  
First Time

Abstract By means of a unique artificial pit specimen, pit growth on 18 percent chromium-8 percent nickel stainless steel has been measured and characterized. The effects of solution composition, agitation, atmosphere, corrosion current interruption, chloride ion concentration, and inhibitor additions have been investigated. Pit interaction during pit growth has also been determined. The autocatalytic nature of pitting has been verified, and evidence of ion screening at pit sites has been experimentally observed for the first time. 3.2.2

Sign in / Sign up

Export Citation Format

Share Document