Information Fusion Technique for Evaluating Radiation Embrittlement of Reactor Pressure Vessel Steels

A new approach that utilizes the information fusion technique was developed to predict the radiation embrittlement of reactor pressure vessel (RPV) steels. The Charpy transition temperature-shift data is used as the primary index of the RPV radiation embrittlement in this study. Six parameters, Cu, Ni, P neutron fluence, it-radiation time, and irradiation temperature are used in the embrittlement prediction models. The results indicate that this new embrittlement predictor achieved about 66% and 53% reductions, respectively, in the uncertainties for the update General Electric (GE) Boiling Water Reactor (BWR) plate and weld data compared to the Nuclear Regulator, v Commission (NRC) Regulatory Guide 1.99, Rev. 2 (RG1.99/R2). The implications of irradiation temperature effects for the development of radiation embrittlement models are also discussed.