MANUFACTURE OF THE ThO$sub 2$-UO$sub 2$ CERAMIC FUEL PELLETS FOR BORAX-IV

Abstract

Preliminary investigation indicated that it was possible to prepare thoria-urania solid solutions by sintering in air a mixture of Th02 and UsOg-The U3O8 on heating in air was found to disassociate, and when heated with Th02, the resultant body was essentiallya Th02-U02 solid solution. The methods used in preparing and granulating the ThO^ and U3O8 for the BORAX-IV loading are discussed in detail. This material was dry pressed using pressures from 13,000 to 15,000 psi. The pressed pellets were loaded into alumina crucibles andfired to a peak temperature of 1700°C to 1750°C. The fired ware was foimd to have an average apparent density of 9.8 g/cc. The pellets were loaded into aluminiim-1 w/o Ni tube plates and the annulus between the pellet and the tube was filled with lead. After closing the open end of the tube plates, the plates were spot welded into a subassembly.

THE EFFECT OF ADDITIVES ON THE DENSIFICATION OF URANIA-THORIA COMPOSITIONS. Final Report-Metallurgy Program 9.2.2

“…(4)(5)(6) Resulting from this work was the manufacture of a fuel loading for Argonne's BORAX-IV Reactor,(5) In view of the interest in the technique, it was thought desirable to investigate the possibility of improving the sinter ability of the material by adding small amounts of different compounds, as has been done with Th02''' and other materials.…”