Investigations for reducing the release of steam generator materials: experiments and modeling

One of the most common methods of reducing the dose rate in nuclear power plants is to reduce the release that leads to activity build-up. This is done by optimizing the chemistry (by means of pH, addition of elements such as zinc, etc.), composition, or surface conditions of the material. The codes used to predict activity buildup and mitigate the dose rate strongly rely on the representation of various mechanisms. To improve these models our research focused on identifying key parameters in the various stages of the implied phenomena. The influence of surface parameters (work hardening, grain size, surface composition) -the subject of earlier research- is assessed, kinetic laws of corrosion and release are carefully studied, and a model that accounts for all the observed phenomena is presented. (author)