Speaker
Description
Nuclear fusion is a promising option for future large-scale energy supply. There are two main approaches to fusion energy: magnetic confinement fusion (MCF) and inertial confinement fusion (ICF). In 2022 ICF achieved, by the first time, ignition with gain at the National Ignition Facility (NIF). Since then, several campaigns carried out in it have replicated this milestone, achieving successive increases in gain in each of them. These breakthroughs have motivated a notable increase in public and private funding for the development of projects aimed at the conceptualization of commercial power plants.
Despite the achievements, there are still several challenges that need to be addressed prior to up-scaling to a commercial facility. One of them is the development of plasma facing materials (PFMs) able to withstand the combined effects of large thermal loads and radiation environments taking place in these reactors.
In this contribution, we will show the different radiation environments that PFMs have to withstand in ICF reactors operated in the direct drive dry wall approach [1]. We briefly introduce the limitations of coarse-grained W acting as PFM [2]. Finally, based on a combination of experimental and multiscale computer simulation data, we will discuss the capabilities and limitations of alternative W-based materials to act as PFM: nanostructured W, with a large density of grain boundaries [3–7], and W nanocolumns, with a large surface area [8].
[1] J. Alvarez et al., Potential common radiation problems for components and diagnostics in future magnetic and inertial confinement fusion devices, Fusion Engineering and Design 86 (2011) 1762–1765. https://doi.org/10.1016/j.fusengdes.2011.01.080.
[2] R. Gonzalez-Arrabal et al., Limitations for tungsten as plasma facing material in the diverse scenarios of the European inertial confinement fusion facility HiPER: Current status and new approaches, Matter and Radiation at Extremes 5 (2020) 055201. https://doi.org/10.1063/5.0010954.
[3] M. Panizo-Laiz et al., Experimental and computational studies of the influence of grain boundaries and temperature on the radiation-induced damage and hydrogen behavior in tungsten, Nucl. Fusion 59 (2019) 086055. https://doi.org/10.1088/1741-4326/ab26e9.
[4] G. Valles et al., Influence of grain boundaries on the radiation-induced defects and hydrogen in nanostructured and coarse-grained tungsten, Acta Materialia 122 (2017) 277–286. https://doi.org/10.1016/j.actamat.2016.10.007.
[5] P. Díaz-Rodríguez et al., Direct observation of hydrogen permeation through grain boundaries in tungsten, Emergent Mater. 5 (2022) 1075–1087. https://doi.org/10.1007/s42247-021-00344-w.
[6] D. Fernández-Pello et al., Coexistence of a self-interstitial atom with light impurities in a tungsten grain boundary, Journal of Nuclear Materials 560 (2022) 153481. https://doi.org/10.1016/j.jnucmat.2021.153481.
[7] J. Suárez-Recio et al., Early stages of self-healing at tungsten grain boundaries from ab initio machine learning simulations, Commun Mater 6 (2025) 1–14. https://doi.org/10.1038/s43246-025-00945-6.
[8] R. Gonzalez-Arrabal et al., Sputtering fabrication of isolated W nanocolumns: A possible alternative as plasma facing material for nuclear fusion reactors, Nuclear Materials and Energy 40 (2024) 101704. https://doi.org/10.1016/j.nme.2024.101704.