INFLUENCE OF THE NEUTRON FLUX DENSITY ON THE RADIATION EMBRITTLEMENT OF VVER-440/213 VESSEL MATERIALS

摘要

In work on minisamples of the fifth complex of the No. 3 unit of the Kola nuclear power plant it is shown that for neutron fluence 4·10~(23) m~(-2) (operation for approximately 10 yr), neutron flux density 3·10~(15) sec~(-1)·m~(-2) and copper content 0.03% and 0.09% in the metal the shifts of the cold-brittleness temperature are 50 and 120℃, respectively. Under the same irradiation conditions but with neutron flux density 3·10~(16) sec~(-1)·m~(-2), this shift for standard samples is 50℃. These results attest to the state of the vessel material at a given moment in time.