Stephanie Jublot-Leclerc¹, Martin Owusu-Mensah¹, Joël Ribis², Vladimir Borodin³, Ryan Schoell⁴, Ce Zheng⁴, Djamel Kaoumi⁴, Aurélie Gentils¹; ¹CSNSM, Univ Paris-Sud and CNRS, Université Paris-Saclay, ²DEN, SRMA, CEA, Université Paris-Saclay, ³NRC “Kurchatov Institute”, and National Research Nuclear University MEPhI, Moscow, ⁴Department of Nuclear Materials, North Carolina State University

Ferritic-martensitic steels reinforced with oxide dispersions exhibit improved creep and radiation resistance at high temperatures, being promising structural materials for future fission and fusion reactors. Getting basic understanding of nano-oxide precipitation could simplify optimisation of mechanical properties of ODS steels. For this aim, we have studied nano-oxide precipitation in a high purity Fe10wt%Cr alloy using the ion beam synthesis approach. The synthesis of oxide particles was performed by consecutive implantation of keV Ti⁺, and/or Y⁺, and O⁺ ions at room temperature followed by thermal annealing between 600 and 1100°C. The induced microstructural and chemical changes were characterized by conventional TEM, EFTEM, HRTEM and ChemiSTEM. It was found that the nature and size of synthesized nano-oxides strongly depends on implantation and annealing conditions, and particularly on the order of sequence of implantations. The main characteristics of oxide particles are presented and discussed in comparison with the data for conventional ODS steels.