Results from the IAEA co-ordinated research programmes on irradiation embrittlement of reactor pressure vessel steels

摘要

During last twenty years, three phases of the IAEA Co- ordinated Research Programme on Irradiation Embrittlement of Reactor Pressure Vessel Steels was prepared and realized. This programme started with seven countries-counterparts in Phase I butwith 15 countries in Phases II and III. While only one material was tested in Phase I -HSSTP 03 plate of ASTM A-533 B grade, 8 main materials in Phase II were included into study and more than 20 materials for Phase III, all for international studies;additional national materials were included into study, too.The most important results obtained during this study, are:- comparative results from different laboratories in different countries,- high resistance against radiation damage in "advanced steels",- comparison of predictive formulae for transition shifts with experimental results from different steels, use of small scale (Charpy-size) specimens for fracture mechanics testing,- comparison of Charpy impact and fracture toughness shifts,- characterization of the IAEA reference steel JRQ of ASTM A-533-B grade.On the basis of the previously obtained results, new IAEA CRP on "Assuring Structural Integrity of Reactor Pressure Vessels" has been prepared and started. Main task of this programme is a checking existing ASTM procedures for fracture mechanics testingapplied to small scale specimens for further use in reactor pressure vessel surveillance programmes. Main, comparative part of the study will be performed on the IAEA reference steel JRQ.