Materials Creep Qualification Testing for Next Generation Nuclear Reactors

The development of next generation nuclear fission reactors, needed to replace or supplement the current designs of nuclear reactors within the next say 30 years., critically depends on the availability of advanced structural and functional materials systems which have to withstand extreme conditions: high temperatures, intense neutron irradiation, and strongly corrosive coolant environments, in combination with complex loading states and cyclic loading histories. The mechanical performance and reliability of those materials depend in which of the six candidate systems for Generation IV reactors they will be applied. This paper gives an overview of the six selected systems indicating where research on materials integrity, in particular under high temperature creep conditions, is still needed. Using examples taken from research projects in which the authors' laboratory has participated, the materials qualification high temperature testing for three crucial components, reactor pressure vessel and piping, gas turbines and heat exchangers is described in some detail. Finally pointers are derived as to not only the scale of the remaining research needs but also the mechanisms which are planned to be followed in Europe, not to mention globally, to obtain the required data and understanding.