Irradiation and thermal effects on the mechanical properties and solute cluster evolution of Fe-Cu alloy

Fe-1.3at.% Cu alloys were irradiated at 563 K and 773 K to explore the irradiation and thermal effects on the mechanical properties and solute cluster evolution of Fe-Cu alloy. Nanoindentation and atom probe tomography were performed to characterize the hardness and distribution of the solute atoms. The results show that hardness of the alloy increases after irradiation at both temperatures and higher hardness increment is observed at 773 K. Cu clusters with a high number density are formed after irradiation. The volume fraction of the clusters increases from about 0.70% at 563 K to 2.80% at 773 K. These clusters contribute to the hardening of the irradiated alloys. Upon comparing the size and number density of these clusters at different temperatures with different doses of 0, 0.018 and 0.18 dpa, it's found that although both irradiation and thermal effects enhance the precipitation of Cu atoms from the matrix, they have an opposite effect on the evolution of Cu clusters: thermal effect enhances the growth of stable Cu clusters, whereas irradiation primarily promotes the nucleation of the Cu clusters and decomposes the larger Cu clusters.

Automated summary

Fe-Cu alloy was irradiated and thermally treated to investigate its mechanical properties and solute cluster evolution. The irradiation increased the hardness of the alloy, with a higher increment observed at 773 K. Cu clusters with a high number density were formed after irradiation, and their volume fraction increased with temperature. Thermal effect enhanced the growth of stable Cu clusters, while irradiation primarily promoted the nucleation of Cu clusters and decomposed larger clusters.