POINT DEFECTS AND TRANSPORT PROPERTIES IN CARBIDES
Carbides of transition metals and of actinides are interesting and technologically important. The transition metal carbides (or carbonitrides) are extensively being used as hard materials and some of them are of great interest because of the high transition temperature for superconductivity, e.g. 17 K for Nb(C,N). Actinide carbides and carbonitrides, (U,Pu)C and (U,Pu)(C,N) are being considered as promising advanced fuels for liquid metal cooled fast breeder nuclear reactors. Basic interest exists in all these materials because of their high melting points (e.g. 4250 K for TaC) and the unusually broad range of homogeneity of nonstoichiometric compositions (e.g. from UC-0.9 to UC-1.9 at 2500 K). Interaction of point defects to clusters and short range ordering have recently been studied with elastic neutron diffraction and diffuse scattering techniques, and calculations of energies of formation and interaction of point defects became available for selected carbides. Diffusion measurements also exist for a number of carbides, in particular for the actinide carbides. The existing knowledge will be discussed and summarized with emphasis on informative examples of particular technological relevance.
Bibliographic Reference: SOLID STATE IONICS, VOL. 12 (1984), PP. 25-45
Record Number: 1989123014000 / Last updated on: 1987-01-01
Available languages: en