Deposition Parameters On the Property of ZrC Layers in TRISO Particles by Fluidized Bed Chemical Vapor Deposition

In the very high temperature gas-cooled reactors (VHTR), multi-layer coated fuel particles are employed as a fuel to be used under severer irradiation conditions and higher operational reactor temperatures. Tri-isotropic (TRISO)-coated on ZrO2 were conducted by a fluidized-bed chemical vapor deposition (FBCVD) method. For an extended burnup TRISO-coated fuel particle and an advanced type of coated fuel particle, ZrC-coated particle in order to keep their integrity at higher operating temperatures has been developed. This present paper provides experiences and current status of research and development works for the TRISO-coated fuel project. The effect of coating parameter, the deposition temperature and the gas flow rate, on properties of the layer in TRISO-ZrC coated particles was investigated. The uniform ZrC coated layer has been fabricated by adjusting the deposition time during the coating and maintaining the deposition temperature at 1500 °C.