THE EFFECTS OF LOW-DOSES OF 14 MEV NEUTRONS ON THE TENSILE PROPERTIES OF 3 BINARY COPPER-ALLOYS

Miniature tensile specimens of high purity copper and copper alloyed respectively with five atom percent of Al, Mn, and Ni were irradiated with D-T fusion neutrons in the RTNS-II to fluences up to 1.3×1022 nm2 at 363 K. To compare fission and fusion neutron effects, some specimens were also irradiated at the same temperature to similar damage levels in the Omega West Reactor (OWR). Tensile tests were performed at room temperature, and the radiation-induced changes in tensile properties are compared as functions of displacements per atom (dpa). The irradiation-induced strengthening of Cu-5% Mn is greater than that of Cu-5% Al and Cu-5 Ni, which behave about the same. However, all the alloys sustain less irradiation-induced strengthening by 14 Mev neutrons than pure copper. The effects of fission and fusion neutrons on the yield stress of the copper alloys correlate well on the basis of dpa.