An inconsistency in film rupture model of stress corrosion cracking

A critical evaluation of mechanistically based modelling of stress corrosion cracking (SCC) known as film rupture model (FRM) has been made. The model based on surface film rupture is evaluated from both a mechanistic and quantitative standpoint. It is shown that although FRM is based on a real physical phenomenon, this model is not yet (and probably will never be) a correct theoretical description and therefore cannot be recognized as a true model even in those cases where film rupture events forming active-passive transitions could be able to facilitate galvanic pairs and SCC together with other motive forces (e.g., selective slip dissolution due to local excess Gibbs potential, intergranular corrosion, etc.). One of main reasons of such inconsistency is modelling without taking the role of stresses into account to the supply of strain rate providing rupture of surface oxide films (for exposing a bare metal) and the omission of a contribution of mechanochemical effect in dissolution acceleration. (C) 2006 Elsevier Ltd. All rights reserved.