PARTICLE FUEL ELEMENT WITH THREE-LAYER PROTECTIVE COATING OF FUEL MICROSPHERE Russian patent published in 2008 - IPC G21C3/28 G21C3/62 

FIELD: power engineering.

SUBSTANCE: invention is related to the field of nuclear power engineering, in particular, to particle fuel elements of nuclear reactor. Particle fuel element of nuclear reactor with three-layer protective coating of fuel microsphere, in which the first layer from fuel microsphere is made of composition carbon-silicon carbide with content of silicic phase of 30-35 weight % in near-surface zone of external border of layer with depth of 0.05-0.10 from layer thickness and content of silicic phase in remaining part of the first layer of 1-15 weight %, the second layer is made of silicon carbide, the third layer from fuel microsphere is made of composition carbon-silicon carbide, the third layer is made with content of silicic phase of 5-10 weight % in near-surface zone of external border of layer with depth of 0.1-0.2 from layer thickness and content of silicic phase in remaining part of the third layer of 15-30 weight %.

EFFECT: provides increase of operation resource (depth of fuel burning) at the account of reduction of internal pressure of CO and increase of carbide layer corrosion resistance.