Ion Beam Experiments to Emulate Nuclear Fusion Environment on Structural Materials at CMAM

Abstract

One of the major problems not only in nuclear fusion but in all the fields that have to face irradiation damage is to predict the microstructural evolution of all the features that are involved in the good response of the material. In the case of nuclear fusion, it is well known that structural materials that will be a fundamental piece in the future reactor must withstand severe neutron irradiation damage, high temperatures, and cyclic stresses which will result in a reduction of the lifetime of the component. For that reason, a big effort is being done for the scientific community in order to understand the complex mechanisms that lie in the relationship between irradiation damage, microstructure, temperature, stresses, etc. However, neutron irradiation brings inherently transmutation and nuclear activation, which makes extremely hard to study those samples. Therefore, the scientific community is using since long time ago ion beam facilities to emulate the neutron damage, without the worst inconvenience. In this chapter, the authors described briefly the facility located at Centro de MicroAnálisis de Materiales (CMAM), Madrid, and presented afterward some examples of experiments that Spanish Nuclear Fusion Laboratory at CIEMAT has been carrying out related to this matter.

Promoting the Regulatory Acceptance of Combined Ion and Neutron Irradiation for Material Degradation in Nuclear Reactors

“…Several projects expanded self-ion irradiation to include the effects of transmutation in reactor environments, particularly helium gas generation, through dual ion irradiation [52][53][54][55] of structural alloys and in particular, the bi-modal cavity size distributions, were reproduced via the incorporation of the Mansur invariant relationships and the establishment of best practices on operation and monitoring of ion irradiations [57,61]. Other critical features including dislocation loops, precipitation, and radiation-induced segregation were also well represented [62,63] when predictive modeling insight was used to guide the design and interpretation of experimental radiation effects studies.…”

Development of the Dual-Beam Ion Irradiation Facility for Fusion Materials (DiFU)

“…Ion irradiation by single, dual, or triple ion beam facilities [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ] can generate high radiation damage doses within practical timescales (e.g., hours) and is therefore a promising method for the selection of radiation-resistive candidate materials for future fusion power plants and next generation of fission power plants. The key point here is that charged particle irradiation can be used to investigate the effects of neutron radiation damage.…”

Predicting structural material degradation in advanced nuclear reactors with ion irradiation

“…Reactor irradiation campaigns to understand radiation effects on microstructure and properties take years to complete, are extremely expensive, and hampered by the paucity of test reactors, all of which contribute to the historical problem of a glacial pace of research to assess candidate materials. For decades, researchers, individual laboratories and international organizations 2 – 11 have been searching for methods and theory to accelerate radiation damage in structural materials for nuclear energy applications to speed the development of new, more radiation resistant materials. Ion irradiation offers the capability to shrink the irradiation time from many years in a reactor to days using an accelerated damage rate to predict microstructure and mechanical property changes at lower cost 9 , 12 , 13 .…”