Since structural materials used in a fission reactor are subjected to irradiation by high energy neutrons, materials degradation due to irradiation should be taken into account when reactor design and maintenance are made. One of significant issues to be solved for a realization of long term operations beyond 40 years is to clarify the validity of a predictio n of material’s degradation due to long term irradiation that is not experienced yet. Material’s behavior due to 60 years irradiation in a reactor sh...
英字タイトル:
Numerical evaluation of radiation damage in metals under various neutron irradiation conditions

The prediction of the initiation and propagetion of irradiation-assisted stress corrosion cracking is one of the issues for aging countermeasures in nuclear power plants, and it is desirable to improve the accuracy of the prediction. In recent years, theoretical calculations have shown that irradiation defects introduced by neutron irradiation generate internal stress. Therefore, in this research, we calculate the increase of internal stress using the molecular dynamics method when irradiation defects are f...
英字タイトル:
Influence of internal stress by irradiation defect formation on irradiation assisted stress corrosion cracking

Fuel cladding is one of the key components in a fission reactor to keep confining radioactive materials inside a fuel tube. During reactor operation, the cladding is however sometimes breached and radioactive materials leak from the fuel ceramic pellet into the coolant water through the breach. The primary coolant water is therefore monitored so that any leak is quickly detected, where the coolant water is periodically sampled and the concentration of, for example the radioactive iodine 131 (I-131), is...
英字タイトル:
Monte Carlo Modeling for Realizing Optimized Management of Failed Fuel Replacement