Unification of the deterministic and statistical approaches for predicting localized corrosion damage. I. Theoretical foundation

Engelhardt, George R.; Macdonald, Digby D.

doi:10.1016/j.corsci.2004.03.014

Cited by 126 publications

(68 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The theory is readily extended to multiple populations. Based on the mechanism described above, the kinetics of nucleation of metastable pits can be derived by the PDM, [23][24][25] as summarized below. First, the condition for forming a critical cation vacancy condensate at a single breakdown site is expressed as:…”

Section: Kinetics Of Metastable Pit Nucleation In Terms Of the Pdmmentioning

confidence: 99%

“…The theory of the kinetics of metastable pit nucleation in terms of the PDM has been previously developed and has been discussed elsewhere. [23][24][25] Nevertheless, the theory has not been previously evaluated against experimental data. The present paper, for the first time, applies the theory to the analysis of metastable pit nucleation rate data by performing optimization of the kinetic model on multiple sets of independently-determined experimental data on metastable pitting nucleation, which have been published in the literature.…”

mentioning

confidence: 99%

See 1 more Smart Citation

The Kinetics of Nucleation of Metastable Pits on Metal Surfaces: The Point Defect Model and Its Optimization on Data Obtained on Stainless Steel, Carbon Steel, Iron, Aluminum and Alloy-22

Lü

Engelhardt

Kursten

et al. 2016

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

The theory of the kinetics of metastable pit nucleation in terms of the Point Defect Model (PDM) has been applied the first time to describing the evolution of the nucleation rate of metastable pits on a variety of metallic substrates. The PDM successfully accounts for the experimental data that have been reported in the literature on stainless steel, carbon steel, iron, aluminum, and Alloy-22, and which are judged to be reliable and reproducible. Important fundamental parameters related to metastable pitting such as total number density of pitting nucleation sites, dissolution time of the cap over the pit, energy related to absorption of the aggressive ions into oxygen vacancies in the surface of the barrier layer, vacancy condensation rate, and the time at which the nucleation rate of metastable pits is maximum were obtained from the optimization of the PDM on the experimental data, as reported in the present paper. The values obtained for those parameters are in good agreement with values and observations reported elsewhere. The present work successfully demonstrates the capacity of the PDM in accounting for experimental observations of metastable pitting and that the PDM can be applied as an underlying theory for studying and understanding metastable pitting on metal surfaces. The passive state is not perfectly protective and passivity breakdown occurs for various reasons, giving rise to enhanced general corrosion rate or to localized corrosion. Localized passivity breakdown is especially of great concern, because it results in the nucleation and propagation of pits and the subsequent nucleation and growth of cracks provided that there is sufficient tensile stress in the system to initiate crack nucleation at the stress raiser represented by the pit. Metastable pitting, in which passivity breakdown occurs followed immediately by repassivation, is now well-accepted as being an integral part of the process of pitting corrosion on a metal or alloy, culminating in the accumulation of damage via the development of stable pits. It is also well-recognized that repassivation reflects the failure on the part of the pit nucleus to establish a spatial separation between the local cathode and the local anode with the former occurring on the external surfaces and the latter taking place in the nucleus, which is necessary for the buildup and maintenance of the aggressive conditions of high [Cl − ] and high [H + ] (low pH) that cause the pits to grow as stable pits, until they, too, die via delayed repassivation (due to the inability of the pit to maintain separation of the local cathode and the local anode, because of the limited availability of resources of the cathodic depolarizer on the external surfaces).Numerous authors have reported metastable pit nucleation rate data measured under more-or-less well-defined conditions. Williams et al.1-3 reported a good proportional correspondence for Type 304L SS between the nucleation frequency of metastable pits and the frequency of occurrence of propagating (stable) pits, that ...

show abstract

Section: Kinetics Of Metastable Pit Nucleation In Terms Of the Pdmmentioning

confidence: 99%

mentioning

confidence: 99%

The Kinetics of Nucleation of Metastable Pits on Metal Surfaces: The Point Defect Model and Its Optimization on Data Obtained on Stainless Steel, Carbon Steel, Iron, Aluminum and Alloy-22

Lü

Engelhardt

Kursten

et al. 2016

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The critical role of pitting in crack nucleation in power generation, aerospace, and oil and gas applications stimulated considerable effort to understand and to model quantitatively the different stages of damage development, including pit initiation, pit growth, the transition from a pit to a crack and subsequent growth of the crack [3][4][5][6][7][8]. All of these stages present challenges in life prediction modelling but most significantly the transition from a pit to a crack, as the mechanistic process was, until recently, not well characterized.…”

Section: Pit-to-crack Transitionmentioning

confidence: 99%

Corrosion pitting and environmentally assisted small crack growth

Turnbull

2014

Proc. R. Soc. A.

View full text Add to dashboard Cite

In many applications, corrosion pits act as precursors to cracking, but qualitative and quantitative prediction of damage evolution has been hampered by lack of insights into the process by which a crack develops from a pit. An overview is given of recent breakthroughs in characterization and understanding of the pit-to-crack transition using advanced three-dimensional imaging techniques such as X-ray computed tomography and focused ion beam machining with scanning electron microscopy. These techniques provided novel insights with respect to the location of crack development from a pit, supported by finite-element analysis. This inspired a new concept for the role of pitting in stress corrosion cracking based on the growing pit inducing local dynamic plastic strain, a critical factor in the development of stress corrosion cracks. Challenges in quantifying the subsequent growth rate of the emerging small cracks are then outlined with the potential drop technique being the most viable. A comparison is made with the growth rate for short cracks (through-thickness crack in fracture mechanics specimen) and long cracks and an electrochemical crack size effect invoked to rationalize the data.

show abstract

“…[1,2,3]. It has recent important applications in surface science, e. g. for modeling the evolution of corrosion damage at time scales not easily accessible to experiment [4]. In uncorrelated random variable sets, the statistics of the nth extrema is described by the Gumbel's first asymptotic distribution [1,5] if the probability density functions (PDF) of those sets decrease faster than a power law.…”

Section: Introductionmentioning

confidence: 99%

Maximal- and minimal-height distributions of fluctuating interfaces

Oliveira

Reis

2008

Phys. Rev. E

View full text Add to dashboard Cite

We study numerically the maximal and minimal height distributions (MAHD, MIHD) of the nonlinear interface growth equations of second and fourth order and of related lattice models in two dimensions. MAHD and MIHD are different due to the asymmetry of the local height distribution, so that, in each class, the sign of the relevant nonlinear term determines which one of two universal curves is the MAHD and the MIHD. The average maximal and minimal heights scale as the average roughness, in contrast to Edwards-Wilkinson (EW) growth. All extreme height distributions, including the EW ones, have tails that cannot be fit by generalized Gumbel distributions. [1,2,3]. It has recent important applications in surface science, e. g. for modeling the evolution of corrosion damage at time scales not easily accessible to experiment [4]. In uncorrelated random variable sets, the statistics of the nth extrema is described by the Gumbel's first asymptotic distribution [1,5] if the probability density functions (PDF) of those sets decrease faster than a power law. However, deviations from this statistics are expected in fluctuating interfaces if there are strong correlation of local heights. In one dimension, this is the case of Edwards-Wilkinson (EW) interfaces (Brownian curves) [6,7] and other Gaussian interface models The second one is the scaling of the average maximal height, since EW interfaces showed an unanticipated scaling as the square of the average roughness [11], in contrast to several one-dimensional interfaces. This is essential to correlate surface roughness with the extreme events.The aim of this letter is to address those questions by performing a numerical study of 2 the MAHD and MIHD in the steady states of the KPZ and VLDS equations and of various lattice models belonging to those classes in 2 + 1 dimensions. We will show that, for each growth class, two universal distributions are obtained, which may be a MAHD or a MIHD of a given model depending on the sign of the coefficient of the relevant nonlinear term.Combination of data collapse and extrapolation of amplitude ratios (e. g. skewness and kurtosis) of those distributions are used to separate systems with coefficients of different signs. In order to illustrate the drastic effects that asymmetric PDF (i. e. distributions of local heights) may have on MAHD and MIHD, we will discuss their differences in a random deposition-erosion model on an inert flat substrate. We will also show that average maximal and minimal heights is all those models scale as the average roughness, as usually expected, which shows that the EW scaling is an exception [11]. Finally, we will show that KPZ, VLDS and EW distributions cannot be fit by generalized Gumbel distributions.MAHD and MIHD were calculated for the KPZ equation The difference between MAHD and MIHD can be easily explained in a model of random deposition and erosion with an inert flat substrate in the erosion-dominated regime. Let q > 1/2 be the probability of single-particle erosion and 1 − q of deposition, an...

show abstract

Unification of the deterministic and statistical approaches for predicting localized corrosion damage. I. Theoretical foundation

Cited by 126 publications

References 25 publications

The Kinetics of Nucleation of Metastable Pits on Metal Surfaces: The Point Defect Model and Its Optimization on Data Obtained on Stainless Steel, Carbon Steel, Iron, Aluminum and Alloy-22

The Kinetics of Nucleation of Metastable Pits on Metal Surfaces: The Point Defect Model and Its Optimization on Data Obtained on Stainless Steel, Carbon Steel, Iron, Aluminum and Alloy-22

Corrosion pitting and environmentally assisted small crack growth

Maximal- and minimal-height distributions of fluctuating interfaces

Contact Info

Product

Resources

About