Irradiation hardening of Eurofer-97

Lead author Gregory Strangward-Pryce and his colleagues investigated the nature of nano-structuring by high-pressure torsion (HPT) on the irradiation performance of Eurofer-97.  

in 'The effect of high-pressure torsion on irradiation hardening of Eurofer-97' published in Nuclear Materials and Energy, the author and his colleagues deformed the sample to shear strains from 0 to ~230, and then exposed it to Fe³⁺ irradiation doses of 0.01 and 0.1 displacements-per-atom (dpa).  Nanoindentation hardness increased monotonically with deformation, and with irradiation for the undeformed materials.  For both damage levels, less irradiation hardening was observed in severely deformed materials.

The effect was most prominent in the strain range ~60 to ~160, which suggests that nano-structuring may provide an approach for reducing irradiation hardening.