Preliminary Calculated and Experimental Assessments of the Possibility of Using High-Nickel Steels for Pressure Vessels of Next Generation VVERs

The article presents calculated and experimental assessments of the possibility of using Ni-rich RPV steels developed by the JSC NPO Central Research Institute of Machine Building Technology (CNIITMASh) as materials for RPVs of next generation reactors taking into account their structural-phase state, mechanical characteristics, and the possibility of manufacturing a shell with an industrially developed wall thickness. In order to improve service characteristics, it is necessary to apply a complex of measures: change the complex alloying of steels, conduct metallurgical purification from impurities (primarily from phosphorus), and optimize the grain size of castings. The calculation took into account the assumed operating temperature, coolant pressure, strength grade of candidate steels, and their thermal and radiation resistance.