Impact of the ageing of materials on primary damage induced by different neutron spectra
Résumé
The recent nuclear evaluations like the Thalys based Evaluation Nuclear Data Library (TENDL) are now able to accurately estimate either from Monte Carlo simulations or experimental results the many elastic and inelastic neutronatoms interactions and allow calculating more realistically primary damage induced by nuclear reactions. Even if these calculations do not take into account relaxation processes occurring at the end of the displacement cascade, they can accurately describe primary and recoil spectra in different reactors or ion beam accelerators. Since neutrons are sensitive to isotopes and not to chemical elements, these spectra must be calculated taking into account all neutron-isotopes interactions separately and then be summed over the relative abundance of different isotopes forming chemical elements. Such a procedure is applied in the DART code developed to compare irradiation in different facilities. Such a procedure gives an accurate estimation of primary damage induced by different fluxes within the Binary Collision Approximation using the TENDL-2015 library allowing to mimic primary damage produced in different nuclear facilities with ion beams. In this work we discuss the potentiality of such an approach computing primary damage in Ni based steel springs of nuclear reactors for different irradiation times, pointing out the importance of ageing, i.e the modification of isotopic abundance of Ni isotopes with the irradiation fluence, on these spectra. This calculation taking into account accurate neutron isotope cross sections is crucial to determine the nature and the energy of ions used in ion beam facilities to mimic the micro structural evolution of actual and future materials for nuclear plants.
Domaines
Physique [physics]
Origine : Fichiers produits par l'(les) auteur(s)