Microstructural evolution and swelling of copper alloys under ion irradiation

The microstructural evolution and swelling of pure copper, a precipitation-hardened alloy Cu-Cr-Zr-Mg, and the dispersion strengthened (DS) alloys Cu-Mo, MAGT-0.2 and MAGT-0.05 have been investigated after ion irradiation to doses of 3–150 dpa at irradiation temperatures of 260–600°C. It was shown that for pure copper the maximum swelling temperature was approximately 500°C and the swelling rate was 0.3–0.5% (dpa) −1 . In the Cu-Cr-Zr-Mg alloy voids have not been found for doses up to 150 dpa, but great changes in dislocation structure and phase composition have been observed. In DS-type alloys void formation has been found to depend on the dispersion particle size and concentration. In MAGT-0,2 alloy voids have not been found up to a dose of 150 dpa. However in MAGT-0.05 alloy voids have been observed at 100 dpa. Irradiation produces a redistribution of the dislocation structure and subgrain formation.