Correlation between changes in microhardness and phosphorus segregation during post-irradiation annealing

This paper describes the effect of post-irradiation annealing (PIA: 573-873K for 10h) on the microhardness and intergranular P segregation in P doped and Cu-P doped iron alloys containing residual S. Hardening and softening occurred during PIA at lower and higher temperatures, respectively. PIA-induced hardening was more profoundly observed in the Cu-P doped alloy. Intergranular P enrichment was achieved by lower temperature PIA and P desegregation associated with S segregation dominated at higher PIA temperatures in both the alloys. Changes in the microhardness and intergranular P segregation induced by the PIA were found to be correlated with each other although the Cu-P doped alloy showed more scatter. The dynamic interaction between solute and defects in the grain interior and near grain boundaries during the PIA is discussed in order to explain the experimental observation