BRAZED DISPERSION STRENGTHENED COPPER: THE EFFECT OF NEUTRON IRRADIATION AND TRANSMUTATION ON BOND INTEGRITY

摘要

Four types of brazes were used to join sheets of GLIDCOP? A125 Miniature tensile specimens were fabricated from the joints and irradiated under various conditions for a study of their response to high temperature neutron irradiation in FFTF Two of the sets of specimens, brazed with TiCuAg and TiCuNi, were found to possess low quality joints because of excessive diffusion of silver into the base metal in the case of the TiCuAg, and melting of the base metal in the case of the TiCuNi. Joints produced with a CuAu braze were satisfactory for the unirradiated state, but transmutation of Au to Hg affected the integrity of the joints irradiated in a below-core position where the transmutation rate per dpa was rather high. A CuAg braze yielded satisfactory joints in the unirradiated state and held up well when the irradiated specimens were tested. However, transmutation of Ag to Cd leads to a high residual radioactivity that may limit the usefulness of this braze after exposure to neutron irradiation.