Effect of initial oxygen content on the void swelling behavior of fast neutron irradiated copper

Density measurements were performed on high purity copper specimens containing ⩽10 and ∼90 wt ppm oxygen following irradiation in FFTF MOTA 2B. Significant amounts of swelling were observed in both the low-oxygen and oxygen-doped specimens following irradiation to ∼17 dpa at 375 °C and ∼47 dpa at 430 °C. Oxygen doping up to 360 appm (∼90 wt ppm) did not significantly affect the void swelling of copper for these irradiation conditions. This implies that surface energy reduction associated with oxygen segregation and chemisorption on void surfaces is not a significant factor controlling the void swelling behavior in copper irradiated with neutrons to high doses at ∼400 °C.