Two model Fe-Cu binary alloys, Fe-0.3Cu and Fe-0.6Cu, were irradiated with fission neutrons at doses ranging from 4 x 10-6 to 0.16dpa at ∼573K in order to investigate the formation of Cu precipitates and microstructural evolution. The Cu content only affected the formation of Cu precipitates and microvoids at low doses. In Fe-0.3Cu, the formation of microvoids and Cu precipitates initiated at doses of 1.2 x 10-4 and 4 x 10-5dpa, respectively. On the other hand, the formation of microvoids started at a dose of 4 x 10-4dpa in Fe-0.6Cu, and Cu precipitates were formed even after irradiation to 4 x 10-6dpa. On further irradiation, the difference in the formation of Cu precipitates and microvoids was small. Microvoids grew with increasing irradiation dose up to 3 x 10-3dpa in both alloys. Prominent aggregation of Cu atoms occurred upon irradiation from 3 x 10-3 to 1.6 x 10-2dpa and the microvoids shrank. The Cu precipitates no longer grew, and microvoids nucleated and grew in the matrix above a dose of 1.6 x 10-2dpa in both alloys. The present studies clearly revealed the relationships between the formation and growth of Cu precipitates and microvoids with irradiation dose.

Formation of Cu Precipitates and Vacancy Clusters in Neutron-Irradiated Fe-Cu Alloys. Q.Xu, T.Yoshiie, K.Sato: Philosophical Magazine Letters, 2008, 88[5], 353-62