Author/Authors :
RalfAhlstrand، نويسنده , , MichelBièth، نويسنده , , ClaudeRieg، نويسنده ,
Abstract :
Decisionsregardingtheverificationofdesignplantlifetimeinvolveadeterminationofthecomponentandcircuitcondition.Neutronembrittlementofreactorpressurevessels(RPV)becomesacrucialconsiderationforcontinuedsafeplantoperation.Since1991,theEuropeanCommission(EC)hasfinancedasignificantnumberofprojectsinthisarea,inparticularthroughtheTACISandPHAREprogrammes.InNuclearSafetysupportprogrammesthecountriesmainlyconcernedareRussia,Ukraine,Armenia,andKazakhstanfortheTACISprogramme,andBulgaria,CzechRepublic,Hungary,SlovakRepublic,Lithuania,RomaniaandSloveniaforthePHAREprogramme.Thecorrespondingresultsoftheseprojectsonneutronembrittlementhavecontributedtoabetterunderstandingoftheavailabledataandtheiruncertainties.RecentconfirmationsoftheirradiationtemperaturesofthesurveillancespecimensintheoperatingVVERnuclearpowerplantsshowthatthesurveillancespecimenscanbeusedfurtherforthevalidationofthecurrentandtheexpectedneutronembrittlement.TakingintoaccountthelatestresultsasabaselineforthedevelopmentofthenecessarymaterialdatatobeusedforupgradedRPVintegrityassessment,twonewTACISprojectsarebeinglaunched,jointlywithRussiaandUkraine,whosescopeis:
