QUATERNARY SYSTEM U-C-O-N AT 1700 C

The quaternary system U‐C‐O‐N was examined at 1700°C by microstructural and X‐ray analyses of sintered powder compacts. Subliquidus phase relations, oxycarbonitride solid solution lattice parameters, and equilibrium pressures of N2 and CO were studied. Although the emphasis was on the solid‐solution field in the uranium monocarbide‐mononitride‐monoxide region, phase fields in the uranium‐rich region and the carbon‐nitrogen‐oxygen‐rich region were examined. Nineteen fields were established experimentally, and their boundaries were located. Two other fields are postulated on the basis of phase rule and topological requirements. An isothermal phase diagram of the system is proposed. Copyright © 1969, Wiley Blackwell. All rights reserved