Adwanced Water Reactor Progran. Seven reaction couples were studied for 60 days at 600 and 800-C:. graphite; lead with Zircaloy-2 amd stainless steel; amd graphite with Zircaloy-2. No reactions were observed at 600 C and only lead-Zircaloy-2 appeared to react at 8OO C. Fast Power Breeder Reactor Program. EBR-I Mark III core is being fabricated. Tests in Borax-rV on sheetu showed fracturing dependent on UO/sub 2/ content. Non-destructive testing development continued. Alloying with Ru showed no improvement in corrosion properties of U. Corrosion of M388 A1 alloy as affected by Vhosphate, pH, and flow rate were studied. Production, Trcatment, amd Properties of Materials. Plastic deformation and thermal conductivity of U single crystals was studied. Ihvestigation of recrystallization of alphaU without a texture change continued. Tests of French uranium are reported. Barrier layers of UO/sub 2/ were found in sputtering of Zr and U onto U, probably resulting from impurities in the argon used. Phase traasformations in the U-C system were studied, and gamma U lattice parameters for 900k C annealed amd water quenched U-Mo-Ru are given. Studies are also reported on the Zr corrosion mechanism and sintering of ceramic materials. (For preceding period see ANL5717.) (T.R.H.)