A carbon-carbon composite brazed with OFHC copper divertor structure h
as been irradiated by neutrons at 673K to 10 dpa. After the irradiatio
n, microstructures and transmutation in the substrate and in the joint
interface region were investigated by TEM. Void formation, which resu
lts in a degradation of brazed material, was prominent in interfaces (
between C/C and a filler metal or between copper phase and silver-copp
er phase) and in OFHC copper substrate.