https://www.powermag.com/welding-and-fabrication-innovations-mitigate-reactor-pressure-vessel-embrittlement-in-nuclear-plant-construction/
New weld filler materials and fabrication processes are capable of eliminating toughness losses associated with fast-neutron irradiation of reactor pressure...
reactor pressure vesselweldingfabricationinnovationsmitigate
https://www.wartsila.com/encyclopedia/term/reactor-pressure-vessel
A reactor pressure vessel in a nuclear power plant is the pressure vessel containing the nuclear reactor coolant, core shroud, and the reactor core.
reactor pressure vessel