Alloy fuels development activities

摘要: The alloy fuels in monolithic form or in inert matrix offer higher density/thermal conductivity and good plasticity. However, alloys could undergo phase transformation due to limited range of phase stability in some cases. The presence of alloying elements as constituents or in the matrix phase alters the stability. Thermal history and local variation in alloying element concentration give rise to morphological changes and volume fraction difference in fuel materials under different fabrication conditions. Different level of technical difficulties arise in preparing the samples of these materials for their microscopy due to high chemical activity, radioactivity and high atomic number resulting in poor reflectivity, transparency and rapid degradation. A lot of caution and care have to be exercised in the preparation, protection and disposal of the samples. Moreover, a great deal of efforts has to be taken in prevention of contamination of delicate and intricate parts of the equipment keeping in mind the ease of maintenance. In this presentation some examples from A1-U, Al-Pu, A1-U{sub 3}Si{sub 2},U-Zr and U-Mo fuel alloys prepared by melt cast or powder metallurgy routes of fabrication have been discussed including micrographs and diffraction patterns