High-temperature materials program. Part B. Sixth annual report

Declassified 21 Sep 1973. This report covers six programs: (1) studies of substoichiometric urania and urania solid solutions above 1700 deg C and their compatibility with refractory metals; (2) refractory-metal fuel element development for operation in non-oxidizing atmospheres; (3) specific materials properly data for various refractory metals and alloys and refractory-metal--UO/ sub 2/ composites; (4) fission product transport processes in refractory-metal fuel systems at temperatures exceeding 1400 deg C; (5) development of long-life, fueled and unfueled, clad metal hydrides, control elements, and shield materials; and (6) the effect of high fuel burnup on BeOstabilized fuel materials. (DLC