Intergranular Stress Corrosion Cracking (IGSCC) is a major concern in Nuclear Power Plants (NPPs). Several components of Pressurized Water Reactors (PWRs) manufactured in nickel alloy 600 started to suffer IGSCC more than 30 years ago. More recently, auxiliary lines made in austenitic stainless steel 316L experienced IGSCC. Therefore, there is a need in better understanding intergranular oxidation, which is a prerequisite to IGSCC.
Since 2015, EDF has developed a phenomenological model to predict the position of intergranular oxidation front as a function of time, temperature, electrochemical potential and percentage of chromium. Parameters of the model have to be calibrated for each type of material.
At the same time, Chimie ParisTech has developed a physical oxidation model known as MSL. Based on McDonald’s point defect model, it describes the growth of uniform oxidation based on the transport of charged species.
The aim of this study is to engage the development of a generic model predicting intergranular oxidation and relying on physical mechanisms by coupling the MSL model with the chemical evolution of grain boundaries experiencing oxidation
Corrosion sous contrainte, Alliage 600, 316L, Oxydation, Modèle