Radiation tolerance of multilayer coating revealed by IBA

Abstract

Nanostructuration has opened the way for designing materials with improved properties by taking advantage of multiple interfaces providing enhanced local physical properties. In this frame, nanostructured materials are envisioned for nuclear applications due to severe environmental conditions (radiation, temperature, corrosion…). Here we report a study based on IBA (RBS and NRA) of a nanometric Cr/Ta multilayer coating demonstrating an extremely high radiation tolerance. TEM was also performed to confirm RBS results.Multilayer coated samples were firstly implanted with helium ions, and NRA analyses revealed that an optimized geometry can accommodate up to 20 at. % of gas without noticeable damage, implanted atoms being probably stored at the Cr/Ta interfaces. Heavy ion irradiation was also performed at room temperature (RT) and 400 °C, mimicking nuclear reactor neutron bombardment. Although we detected the growth of mixing layers at the Cr/Ta interfaces upon irradiation, these newly created layers remain much thinner than those produced at a single interface, preserving the initial multilayer arrangement.