Fabrication and Thermal Conductivity of Boron Carbide/Copper Cermet

Studies on fabrication and thermal conductivity of B4C/Cu cermet were made to obtain high performance neutron absorber materials for Liquid Metal-cooled Fast Breeder Reactor (LMFBR). A mixed powder of B4C and Cu was mechanically blended at high speed thereby a coating layer of Cu was formed on the surface of B4C powder. Then the B4C powder with Cu coating was hot pressed at temperatures from 950 to 1,050°C to form a B4C cermet. A high density B4C/CU cermet with 70 vol% of B4C and relative density higher than 90% was successfully fabricated. In spite of the low volume fraction of Cu. the B4C/Cu cermet exhibited high thermal conductivity which originated from the existence of continuous metallic phase Cu in B4C/Cu cermet.