Investigating radiation damage in nuclear energy materials using JANNuS multiple ion beams
Introduction
Under the auspices of the new Université Paris-Saclay, the multi-ion beam irradiation platform JANNuS for ‘Joint Accelerators for Nanosciences and Nuclear Simulation’ is dedicated to researches in the effects of ions in materials. Its particle beams make it possible to irradiate small samples in a perfectly controlled manner, and thus to observe and quantify the evolution of their microstructure (segregation, precipitation, formation of dislocation loops, cavities, bubbles, etc.) and service properties. JANNuS-Orsay and JANNuS-Saclay have been developed from the origin as two complementary facilities on neighbouring sites (Orsay and Saclay) and they are bound since 2005 by a Grouping of Scientific Interest (GIS) [1]. This platform offers to the international academic community the opportunity to perform fully instrumented irradiation experiments on advanced materials which may be supplemented by in situ characterization techniques such as Transmission Electron Microscopy, Raman or Ion Beam Analysis (IBA) [2]. The actual capabilities combine five electrostatic accelerators for single beam, dual beam and triple beam ion experiments and a Transmission Electron Microscope (TEM) for in situ studies. Such a scientific platform has no equivalent in Europe and plays an essential role for multi-scale modelling of radiation effects in materials. With the scarcity of Material Testing Reactors throughout the world, ion irradiation facilities allow to emulate neutron irradiation and to understand the fundamentals of radiation resistance of nuclear materials. This is of special importance for the present and future nuclear industry. As an example, Ref. [3], [4] describe the need to predict the modification of materials under irradiation and to validate their radiation resistance.
In situ Transmission Electron Microscopy is a speciality since the early 1980’s [5] of the CSNSM lab (joint research unit of CNRS/IN2P3 and Université Paris-Sud) located in Orsay, France. A 120 kV Philips EM400 TEM and a 190 kV homemade ion implanter (called IRMA [6]) were connected together under the guidance of Dr. Marie-Odile Ruault, allowing in situ observations of modification of materials under ion beam. Several research projects took place mainly on ion beam synthesis in semiconductors and metals using this peculiar equipment e.g. [7], [8], [9], [10]. A new 120 keV Philips CM12 microscope equipped with Energy-Dispersive X-ray Spectroscopy was installed in 1994 [11] and researches were still focused on ion beam synthesis in silicon for microelectronic applications e.g. [12], but also dedicated to nuclear materials e.g. [13], [14], [15]. The facility was updated in 2006 [16] with the arrival of a new FEI Tecnai 200 kV G220 TEM and the construction of a new ion beam line connected to ARAMIS [17], a 2 MV Tandem/Van de Graaff homemade accelerator, built in the late 80’s. This exceptional facility that includes the TEM and the two ion beam lines coming from the IRMA ion implanter and the ARAMIS ion accelerator has been called JANNuS-Orsay. It is part of the SCALP accelerators platform of the CSNSM lab, where single ion implantation/irradiation and ion beam analysis are also available [18].
The DMN department of the CEA Paris-Saclay has been developing for many years modeling tools from the atomic to the macroscopic scale in order to validate the resistance of nuclear materials under the extremely harsh conditions which they encounter in service, in particular irradiation effects, and to design innovative materials for advanced nuclear systems [19]. These models rely on high-performance numerical methods and on fully controlled characterization techniques at the same scales. In line with this technological and scientific approach, the SRMP has designed the JANNuS-Saclay triple ion beam irradiation facility as a key tool to understand the physical mechanisms of neutron radiation damage, and to validate the multiscale modeling of the macroscopic events of materials aging [20].
After a brief technical description of each facility, this paper gives selected examples of recent research studies related to nuclear materials for existing and future reactors that have been performed at JANNuS.
Section snippets
Description of the equipments
Ion accelerators have been used by material scientists for decades to investigate radiation damage formation in nuclear materials and thus to emulate neutron-induced changes e.g. [21], [22]. The versatility of conditions in terms of particle energy, dose rate, fluence, is a key asset of ion beams allowing for fully instrumented analytical studies. In addition, very short irradiation times and handling of non-radioactive samples dramatically curtail the global cost and duration as compared to
Examples of radiation damage investigations in nuclear materials at JANNuS
In the last decade, many materials of interest for the nuclear industry have been investigated at the JANNuS platform. A non-exhaustive list includes: nuclear fuel and surrogates such as uranium dioxide [30], [31], [32], [33]; neutron absorber like B4C [34], [35]; structural alloys for present, advanced and future fission and fusion systems as well as model metals such as iron, Fe-Cr alloys and ferritic-martensitic steels [36], [37], [38], [39], ODS steels [40], [41], [42], [43], [44], [45],
Conclusion
In France, under the auspices of the Université Paris-Saclay, the JANNuS platform for Joint Accelerators for Nanosciences and Nuclear Simulation comprises five ion implanter and electrostatic accelerators with complementary performances. At CSNSM (CNRS/IN2P3 and Univ Paris-Sud, Orsay), a 200 kV Transmission Electron Microscope is coupled to an accelerator and an implanter for in situ observation of microstructure modifications induced by ion beams in a material, making important contribution to
Acknowledgments
The current and former JANNuS staffs are gratefully acknowledged for their unfailing assistance. The on-going support is provided at CSNSM Orsay especially by C. Bachelet, C. Baumier, J. Bourçois, S. Picard, S. Jublot-Leclerc, B. Décamps, but also C.-O. Bacri, L. Delbecq, F. Fortuna, D. Ledu, S. Pitrel, and at CEA Paris-Saclay by F. Leprêtre, G. Adroit, L. Roux, G. Gutierrez, S. Pellegrino, M. Loyer-Prost, A.P. Barabé, H. Martin. We are also thankful to all the users, and especially to G.
References (74)
- et al.
Nucl. Instrum. Methods Phys. Res., Sect. B
(2005) - et al.
J. Nucl. Mater.
(2009) J. Nucl. Mater.
(1994)- et al.
Nucl. Instrum. Methods B
(2019) - et al.
Nucl. Instrum. Methods
(1983) - et al.
Nucl. Instrum. Methods
(1981) - et al.
Appl. Surf. Sci.
(1993) - et al.
J. Nucl. Mater.
(2008) - et al.
Nucl. Instrum. Methods B
(2001) - et al.
J. Nucl. Mater.
(2004)