The properties of oxide-dispersed and spinodally strengthened copper alloys following high-temperature neutron environment exposur

Zone refined marz grade copper and several oxide and spinodally strengthened copper alloys were neutron irradiated to 34 displacements per atom (dpa) at 414$spcirc$C, 50 dpa at 411$spcirc$C, and 32 dpa at 529$spcirc$C in order to assess their suitability for high temperature neutron environment exposure. Density, electrical conductivity, tensile property, and fracture behavior changes were determined with emphasis on the microstructural reasons for the changes observed. The properties of zone refined copper were found to be dominated by the details of the radiation-induced void distribution. The chemical composition and quantity of the dispersed oxide were found to have a substantial influence on the radiation resistance of oxide dispersed copper alloys. Of the oxide dispersed alloys studied, alloys strengthened with increasing volume fractions of alumina were found to be the most radiation resistant. Laser welding was found to be an ineffective method by which to join oxide dispersed copper alloys for nuclear applications. Spinodally strengthened alloys were found to exhibit improved properties following irradiation. Along with oxide dispersed alloys, spinodally strengthened alloys show merit for use in high temperature neutron environments although their low initial conductivity may be a limitation.