Stress corrosion cracking Model

Pauchard V, Grosjean F, Campion-Boulharts H, Chateauminois A (2002) Application of a stress corrosion cracking model to the analysis of the durability of glass/epoxy composites in wet environments . Composites Science and Technology, 62, 493 98. 

Smith, T., A Capillary Model for Stress-corrosion Cracking of Metals in Fluid Media, Corros. Sci., 12, 45 (1972)... 

The implication of the foregoing equations, that stress-corrosion cracking will occur if a mechanism exists for concentrating the electrochemical energy release rate at the crack tip or if the environment in some way serves to embrittle the metal, is a convenient introduction to a consideration of the mechanistic models of stress corrosion. In so far as the occurrence of stress corrosion in a susceptible material requires the conjoint action of a tensile stress and a dissolution process, it follows that the boundary conditions within which stress corrosion occurs will be those defined by failure... 

Ford, F. P., Modelling and life prediction of stress corrosion cracking in sensitized stainless steel in high temperature water , Proc. of ASME Fall Meeting, 1985... 

The following schema describes the models of stress corrosion cracking mechanisms. 

In metal alloys the combination of stress and environment can also lead to premature failures, indicated as Stress Corrosion Cracking, SCC [1]. The influence of the environment on SCC is generally of a chemical nature a chemical reaction occurs between the metal and the environment. Most of the research published on the ESC of polymers focuses on ESC in which the environment influences the material only physically [2-8]. In such cases the mechanism of ESC is studied and models are established for ESC prediction [9]. These models for physical ESC are based predominantly on the solubility parameters of the considered polymer/environment combination. In other words, ESC is mainly a consequence of polymer softening, i.e. it is a reduction of the interaction between the polymer chains that lowers the yield stress. 

As an example of application of (l)-(4) let us consider a cantilevered piping run with cracked root section. Two kinds of cracks presented in Fig.l and 2, respectively, used for modelling of stress corrosion cracks in boiling water nuclear reactor steam supply systems will be considered in present study. 

WILLIAM H. SMYRL is Professor of Chemical Engineering and Materials Sciences and Associate Director of the Center for Corrosion Research at the University of Minnesota. He received his Ph.D. (chemistry) at the University of California, Berkeley, and spent 3 years at the Boeing Scientific Research Laboratories and 11 years at Sandia National Laboratories. He joined the faculty of the University of Minnesota in 1984. His research interests are modeling of corrosion processes, in situ techniques for metal-metal oxide interface studies, digital impedance for faradaic analysis, stress corrosion cracking, polymer-metal interfaces, and electrochemical processes. 

Krafft [4] and Krafft and Mulherin [5] later extended the TLI model to describe stress corrosion crack growth. Crack growth was viewed in terms of the instability of tensile ligaments where their lateral contraction was augmented by uniform chemical dissolution of the tensile ligaments. For sustained-load crack growth in an inert environment, on the other hand, the reduction in the cross-sectional area of the ligaments would be associated with the creep rate (Landes and Wei [2], Yin et aL... 

Linearly increasing stress test Examples of Stress Corrosion Cracking see Models... 

Atomic surface mobility model Metallurgy of Stress Corrosion Cracking... 

T. Nakayama, M. Takano, Application of a slip dissolution-repassivation model for stress corrosion cracking of AISI 304 stainless steel in a boiling 42% MgCb solution. Corrosion 42 (1986) 10-15. 

E.M. Gutman, An inconsistency in film mpmre model of stress corrosion cracking, Corros. Sci. 49 (2007) 2289-2302. 

H. Vogt, M.O. Speidel, Stress corrosion cracking of two aluminum aUoys a comparison between experimented observations and data based on modeling, Corros. Sci. 40 (1998) 251—270. 

F. Gutierrez-Solana, J. Gonzalez, J.M. Varona, M.V. Biezma, Modeling the stress corrosion cracking oflow alloy steels, Corros. Sci. 35 (1993) 499-505. 

R.W. Staehle, Predictions and experimental verification of the slip dissolution model for stress corrosion cracking of low strength alloys, in R.W. Staehle (Ed.), Stress Corrosion Cracking and Hydrogen Embrittlemen of Iron Base Alloys, In NACE-5NACE, Houston, TX, 1977, pp. 180-207. 

For some material-environment combinations it has been shown that accelerated anodic dissolution of yielding metal is the significant mechanism. This is the case for austenitic stainless steels in acidic chloride solutions. In these steels, plastic deformation is characterized by a dislocation pattern giving wide slip steps on the surface. For such systems, Scully [7.50] has proposed a model for initiation and development of stress corrosion cracks, which has been supported by other scientists [7.51]. The model in its simplest form is illustrated in Figure 7.52. A necessary condition is that flie surface from the beginning is covered by a passivating film (A). 

Blain, C., A. Barros, A. Grail, and Y. Lefebvre (2007). Modelling of stress corrosion cracking with stochastic processes-application to steam generators. Proceedings of European Safety and Reliability Conference, Esrel 2007, June 25-27 2007, Stavanger, Norway, Eds Terje Aven Jan Erik Vinnem, ISBN 978-0-415-44786-7 3, 2395-2400. 

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