ABSTRACT
In response to potential corrosion risks or to actual corrosion problems, new materials and fabrication processes have been adopted and system operating parameters adjusted accordingly, e.g. through water chemistry control. For many years now, in response to multiple types of corrosion-induced damage encountered in Pressurized Water Reactors components, a major research and development effort has been underway to determine the best materials, fabrication processes, and operating conditions with which to combat corrosion phenomena. Deterioration of hard facing alloys has also been observed in some cases. This type of corrosion can result not only in loss of leaktightness or binding, but also in elevated dose rates from cobalt-60 released into the reactor coolant system, since most hard facing alloys are cobalt-based. Certain operators are still paying for the failure to observe these principles in the past. In this domain, as in many others, numerous problems could have been avoided by closer collaboration between research laboratories and plant constructors or operators.
