Analysis of embrittlement of WWER-1000 RPV materials

Analysis of embrittlement for WWER-1000 RPV materials is performed on the basis of available and original experimental data. Contributions of thermal aging and neutron irradiation to embrittlement are considered for base and weld metals. Equations have been obtained for the shift of the critical temperature of brittleness as a function of irradiation time and neutron fluence. For weld metal with high nickel content the dependence of the radiation embrittlement coefficient on the content of alloying elements affecting material embrittlement such as nickel, manganese and silicon has been obtained.