Grain Boundary Segregation in Commercial Nuclear Reactor Pressure Vessel Steels
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چکیده
Grain boundary (GB) segregation of impurity/solute atoms in surveillance test specimens of a commercial western-type pressurized water reactor pressure vessel (RPV) steel has been observed by using state-of-the-art 3D atom probe (3DAP) field ion microscope (laser-assisted local electrode-type atom probe: laser-LEAP). The GB segregation is considered to be an origin of the embrittlement of the RPV steels without hardening. After the low dose irradiation, P, C and Mo atoms are segregated on GB. After the high dose irradiation, the segregation of Si, Mn and As atoms, in addition to P, C and Mo, is observed.
منابع مشابه
Intergranular Segregation in the Pressure Vessel Steel of a Commercial Nuclear Reactor Studied by Atom Probe Tomography
Solute/impurity segregation and precipitation at grain boundaries (GBs) in a nuclear reactor pressure vessel (RPV) steel were investigated using laser-assisted atom probe tomography (APT): RPV surveillance test specimens irradiated in a commercial nuclear reactor to neutron doses of 0.83 © 1019 n·cm12 (low-dose) and 5.1 © 1019 n·cm12 (high-dose), corresponding to in-service exposure of 35 and 3...
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