HIGH THERMAL CONDUCTIVITY GRAPHITE FOR THE INTERNATIONAL THERMONUCLEAR EXPERIMENTAL REACTOR FIRST WALL

DOE NEEDS TO DEVELOP HIGH THERMAL CONDUCTIVITY, IRRADIATION STABLE FIRST WALL ARMOR FOR THE INTERNATIONAL THERMONUCLEAR EXPERIMENTAL REACTOR (INTER). A HIGH THERMAL CONDUCTIVITY GRAPHITE WILL BE DEVELOPED IN PHASE I BY ADDING METALS IN THE PREMIX DURING FABRICATION. METALS SUCH AS TITANIUM, SILICON, AND BORON THAT ARE KNOWN TO FORM CARBIDES WILL BE USED. THE METAL-LOADED GRAPHITES WILL BE HEAT TREATED TO DISSOCIATE THE CARBIDES AND DEPOSIT LARGE "SKELETAL" GRAPHITE CRYSTALS IN THE MICROSTRUCTURE TO IMPROVE THE THERMAL CONDUCTIVITY. IMPREGNATION WITH HIGH CHAR YIELD PITCHES AND INFILTRATION WITH A HYDDROCARBON GAS THAT DEPOSITS PYROLYTIC CARBON WILL BE USED TO IMPROVE DENSITY, THERMAL CONDUCTIVITY, AND MECHANICAL PROPERTIES AFTER FORMATION OF THE GRAPHITES. THE IMPROVED GRAPHITES WILL BE CHARACTERIZED BY MEASURING THERMAL AND MECHANICAL PROPERTIES. THE IMPROVED GRAPHITES WILL BE EVALUATED FOR IRRADIATION BEHAVIOR. SELECTED STRUCTURES WILL BE IDENTIFIED IN PHASE I FOR FURTHER STUDY IN PHASE II. THE MOST PROMISING MATERIALS DEVELOPED IN PHASE I WILL BE IRRADIATED DURING PHASE II.