Nuclear Materials: Fission (RPV steels)

RPV steels

Solute clustering is known to play a significant role in the embrittlement of Reactor Pressure Vessel (RPV) steels.  Primarily, research has focused on the deleterious effects of copper.  However, it is becoming increasingly evident that low-copper steels embrittle, specifically due to the role of nickel and manganese in cluster formation.  In this study the effects of long term thermal ageing on the microstructure and mechanical properties of RPV steels are investigated utilizing atom probe tomography (APT).  This research focuses on low copper steels in order to highlight the clustering behavior of nickel and manganese.  To date the steels have been thermally aged for 10,000 hours at various temperatures (330°C, 365°C, and 405°C).

 AP map of a high copper RPV steel with copper enriched precipitates. This steel has been thermally aged for 10,000 hours at 365 degrees Celsius
 
For more details on this project, please contact  B. Jenkins or Michael Moody.