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Fusion reactors, advanced fission reactors and high power accelerator spallation targets subject materials to damaging particle irradiation. Although these technologies derive their utility from different nuclear reactions and divergent applications, they experience many common features. Further, the physical mechanisms of radiation response are cross-cutting. For example, swelling, phase instability, hardening, flow localization, and embrittlement must be understood in order to estimate component lifetimes. Additional commonalities include reliance on the same classes of materials and sometimes on the identical alloy for critical components. In addition, databases supporting designs are mainly derived from the same relatively few irradiation facilities and from similar types of experiments. Opportunities are examined for coordinated efforts. Emphasis is placed on the development of fundamental knowledge to support alloy design strategies for resistance to irradiation and to form a scientific basis to develop better materials. [Copyright &y& Elsevier]

Abstract: The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is an accelerator-based pulsed neutron source that produces high-energy spallation neutrons by bombarding liquid mercury flowing through a stainless steel target vessel. During operation the proton beam and spallation neutrons produce radiation damage in the AISI 316L austenitic stainless steel target vessel and water-cooled shroud. The beam pulses also cause rapid heating of the liquid mercury, which may produce cavitation erosion damage on the inner surface of the target vessel. The cavitation erosion rate is thought to be highly sensitive to beam power and predicted to be the primary life-limiting factor of the target module. Though cavitation erosion and radiation damage to the target vessel are expected to dictate its lifetime, the effects of radiation damage and cavitation erosion to target vessels in liquid metal spallation systems are not well known. Therefore preparations are being undertaken to perform post-irradiation examination (PIE) of the liquid mercury target vessel and water-cooled shroud after end-of-life occurs. An overview of the planned PIE for the SNS target vessel is presented here, including proposed techniques for specimen acquisition and subsequent material properties characterization. [Copyright &y& Elsevier]