Development of fuel cladding material for the next-generation nuclear power reactor

The capability for the fuel cladding made of silicon carbide (SiC) fiber-bonded ceramic composite, which consists of a close-packed structure of silicon carbide fiber, was studied. The microstructure was composed of the close-packed structure of the fiber with the interfacial carbon layer. For the thermomechanical properties, SiC composite indicated higher thermal conductivity than zirconium alloy and a relatively high tensile strength. Moreover, fracture toughness of SiC composite was higher than that of other monolithic ceramics owing to fiber layer debonding. The observed characteristics were favorable for SiC composite to be a candidate material applicable to the next-generation reactor. (author)