High power millimeter and submillimeter wave material processing

Boron carbide (B/sub 4/C) is one of advanced materials and is being used in a wide rage of applications. The unique feature of this material is its large neutron-absorbing cross-section. Some of its most prominent applications are controlling rods in nuclear reactors and radiation protection. 24 GHz microwave processing for B/sub 4/C ceramics were performed under flowing argon gas using the sintering system. The sintered samples were characterized by the density, the shrinkage and SEM micrographs of fracture surface. Above the temperature of 2000/spl deg/C, the shrinkage and the grain grows are observed.