Development of radiation resistant materials for advanced nuclear power plant

Abstract

A unique feature of the environment of nuclear power reactors is the presence of high energy neutron radiation, which can lead to degradation processes in the materials of critical components. An understanding of the operative elevated temperature radiation damage mechanisms enables these effects to be minimised by appropriate alloy selection together with compositional optimisation. An overview of these aspects relevant to advanced fission and fusion reactor systems is presented. Several key examples are highlighted and include radiation embrittlement of low alloy pressure vessel steels for pressurised water reactors, coating designs for fuel in high temperature pebble bed reactors, and selection and design of low activation materials for proposed tokomak fusion reactor devices. In addition, void swelling, non-equilibrium solute segregation and radiation induced precipitation processes in alloys at high displacement doses and relevant to several reactor systems are covered. Likely trends in future nuclear power plant design and associated materials requirements are discussed.

Gas atomized precursor alloy powder for oxide dispersion strengthened ferritic stainless steel

“…The structural materials in fourth generation reactors will face an increasingly severe environment. Materials located in the reaction core of thermal and fast reactors will be subjected to neutrons with energies ranging from several MeV down to ~0.025 eV and ~10 KeV, respectively [38]. The pressures inside the reaction vessel will range with rector type from ~0.1-25MPa [16].…”

“…A tungsten (W) addition was usually included as a solid solution strengthener for the Fe-Cr matrix phase, as well [115]. These iron (Fe) based alloys are being considered as structural materials for use in future generation power reactors [9,16,38,65]. However, a major drawback to the widespread use of Fe-based ODS steels stems from the rather expensive cost associated with finished forms of these alloys (e.g.,~$340USD/kg for PM2000) [203].…”

“…Oxide dispersion strengthened (ODS) ferritic stainless steel alloys are being considered for structural components within future generation power reactors [9,16,38,65]. These alloys have demonstrated superior elevated temperature strength and creep resistance [1,2,202].…”

“…For this reason, these alloys are being considered for high temperature applications within future generation thermal power reactors [8,9,16,38]. The improved mechanical properties associated with ODS alloys stems from interactions between nano-metric oxide dispersoids and dislocations within the alloy microstructure [3,70,80].…”

“…Oxide dispersion strengthened (ODS) ferritic stainless steel alloys are being considered for elevated temperature applications within several types of future generation power plants [8,9,22,38]. These alloys contain a large number density of nano-metric oxide particles that impede dislocation movement and stabilize the intrinsic strengthening effect of the sub-grain structure [3,70,80].…”