Research and development on coated fuel particle for HTGR

The research and development of coated fuel particles is one of the most important part in the research work of the high temperature gas cooled reactor. Coated fuel particles are made in fluidized bed furnace by chemical vapor deposition. The relationships between the coating parameters and the properties of the coated fuel particles have been systematically investigated. The optimum coating technology of porous pyrocarbon layer (at deposition temperature of 1350 degree C, C2H2 concentration of 85%), dense pyrocarbon layer (at deposition temperature of 1435 degree C, C3H6 concentration of 25%) and silicon carbide layer (at deposition temperature of 1600 degree C, CH3SiCl3 concentration of 1.80%) had been obtained by controlling the deposition factors according to the formula summarized from experiments. The TRISO type coated fuel particle with density of 0.99 g/cm3 for porous pyrocarbon layer, with density of 1.89 g/cm3 for dense pyrocarbon layer and with density of 3.21 g/cm3 for SiC layer has been fabricated