Summary of results from the ORNL ion irradiation program

The ion irradiation program is focused on developing an understanding of the mechanisms by which irradiation changes the physical and mechanical properties of metals and alloys. The scope includes void and bubble swelling, irradiation creep, and embrittlement. Theory and experiment are brought to bear on these phenomena. Dual and triple beam ion irradiations are carried out at the 5 MV Van de Graaff - 0.4 MV Van de Graff Facility. Heavy ions (e.g., Ni, Fe, Ti, Al) are accelerated with the 5 MV Van de Graaff and light ions (He, D2, H2) are accelerated with the 0.4 MV Van de Graaff. To make the depth of the light ion implantation span the region of radiation damage caused by the heavy ions the energy of the light ion is varied continuously by cycling the terminal voltage from 200 to 400 kV