METALLURGY DIVISION QUARTERLY PROGRESS REPORT FOR PERIOD ENDING JANUARY 31, 1951

The stability and corrosion resistance of thorium exposed to eutectic NaK were investigated. Satisfactory results on thorium tube or rod fabrication by means of extrusion were obtained. Rolling and swaging thorium presented no difficulty but drawing proved unsuccessful. Strainhardening values of iodide thorium were about half of those of Ames thorium. The fubrication of unanium tubing by extrusion was successful in the alpha but not in the gamma nange. By increasing the extrusion ratio, an increaae in the strength of the STA410! fiber texiure with respect to that of the STA010! component and an increase in sharpness of both resulted. Static corrosion tests using a two-component system was initiated. The characteristics of a plate which is to be fabricated into a fuel element tube were determined and methods for fabrication of such a plate are discussed. (See also ORNL-910(Del).) (C.J.G.) Preliminary investigations on SAP (sintered aluminum powder) alloys are reported. The mechanical properties of SAP at elevated temperatures are oniy slightly altered by prolonged heating. Its structaral stability is not effected by temperatures at 450 deg C and lower temperatures, blistering starts at 520 deg C and fissures appear in thin walled SAP 930 tubes at temperatures higher than 500 deg C. Thermal cyclings have no influence on the mechanical and structural stability of SAP 930 tabes. Vacuum tightness of SAP tabes can be maintained with temperatures up to 620 deg C. Pressure tightness for an internal pressure of 4 atm of helium is kept at 450 deg C. Thin-walled tubes with twisted fins are made of 8AP 930. Joining of SAP parts by flash and by brazewelding is satisfactory. End closures of the tabes are vacuum tight and show a mechanical strength equal to that of the parent material. SAP shows good corrosion resistance to polyphenyls at 400 deg C. There is no reaction between SAP and UO/sub 2/ after heating at 550 deg C for 56 days. Read and SAP are highly compatible. Neutron irradiation of SAP raises the mechainical strength and lowers the elongation in the material, but the differences between unirradiated and irradiated properties do not appear to be important. (auth