Certain trends in the development of technology and improvement in quality of nuclear fuel (review)

Abstract

The trends in the improvement of the economic characteristics of nuclear power plants, one of which is the prolongation of the reactor campaign, i.e., the period in which the fuel is situated in the active zone under the due increase in its burnup level, are considered. Such an increase can be achieved, specifically, via using fuel with burnable absorbers, as well as by improving the quality of fuel pellets obtained by powder metallurgy. It is necessary to toughen the technical requirements for fuel pellets and improve the technology of their production and the equipment used in their fabrication. It is noted that the works for improving the operational factors of fuel pellets (particularly, lowering their gas release and decreasing the interaction of the fuel with the cladding) are currently mainly oriented to producing pellets with burning absorbers; obtaining the optimal microstructure (porosity and grain size) of the pellets; improving their shape; excluding dust on their surface after smoothing; and stabilizing their properties in regards to geometric sizes, density, and aftersintering.