Mechanical properties of FeCr alloys after neutron irradiation

The mechanical properties of neutron irradiated Fe–Cr ferritic model alloys with various concentrations of Cr and minor solutes (Ni, Si and P) were investigated along with high-Cr ferritic/martensitic steels. The neutron irradiation was performed in a materials test reactor at two temperatures, 290 ∘C and 450 ∘C, reaching a dose of 0.11 dpa. Tensile tests were subsequently performed on small flat specimens. Significant hardening of about 225 MPa was observed only in model alloys containing Ni, Si and P solute atoms, irrespective of the Cr content and the irradiation temperature. These results suggest that Cr solutes play lesser role in irradiation hardening of ferritic/martensitic alloys steels than previously believed, while minor solutes have a clear effect.