A Service Laboratory's View of the Status and Direction of Reactor Vessel Surveillance

Advances in testing techniques and analysis procedures have had a minor impact to date on the conduct of reactor vessel material surveillance programs. However, major thrusts in the near future will be associated with the development of elastic-plastic fracture toughness data on irradiated materials and improvements in analysis techniques for projecting surveillance results to the pressure vessel wall. In this regard, increased emphasis will be placed on the development of R-curves from the results of J-integral tests. Also, efforts will be increased to develop a better understanding of neutron irradiation embrittlement mechanisms, to determine if a time dependency of damage can lead to saturation and to evaluate the significance of small variations in irradiation temperature on the embrittlement response.