Effect of grain boundary planes on radiation-induced segregation (RIS) at near Σ3 grain boundaries in Fe-Cr alloy under ion irradiation
Résumé
Ferritic Martensitic and ODS steels are widely studied for applications in the next generation of nuclear reactor. Their good mechanical properties and corrosion resistance make them good candidates. Under irradiation flux, migration of point defects leads to different mechanisms including radiation-induced segregation (RIS). This type of segregation affects defect sinks such as grain boundaries (GB). Many parameters influence the amplitude of the RIS such as temperature, dose, chemical composition of the alloy… This paper presents the quantification of GB plane variation on RIS. Two different Σ3 (60° <111>) GB were investigate using EBSD and TKD for structural characterization and APT and STEM/EDS for chemical quantification. This work revealed W-shape profiles of Cr across GBs and a heterogeneous precipitation of Cr-C rich particles in GBs planes after irradiation. Our work shows that not only the amplitude but also the sign of the Gibbsian Excess may be affected by the GB plane.
