Mechanical and structural properties of ODS RAF steels submitted to low-energy ions irradiation

The effect of ion implantation on mechanical and structural properties of 12%Cr ODS steel have been investigated. Specimens were submitted to single (He+ or Fe+) and dual ion beam (He+ and Fe+) implantation campaigns. Modification of three mechanical parameters: hardness, Young modulus and yield strength were characterized by means of nanoindentation technique. Structural properties were measured by using Grazing Incidence X-ray Diffraction (GIXRD) method. Correlation between obtained mechanical and structural results have been found. Recorded results show that ion-irradiation causes hardening effect which may be associated with creation of radiation defects and dislocation loops. The weakest effects have been observed for single He-ion implantation, whereas the dual beam irradiation led to significant change of all mechanical parameters. During structural analysis, small shifts of α-Fe peaks have been observed. Reported structural changes can be attributed to the effect of local stress introduced during ion irradiation.