MANUFACTURING PROCESS OF NUCLEAR FUEL PELLETS

The present invention provides a method for manufacturing nuclear fuel pellet, including the steps of: forming a nuclear fuel green pellet with (a) an uranium oxide and (b) mixed powder of an additive inducing grain growth of the pellet during a sintering process; maintaining the atmosphere of oxygen partial pressure not fused with the additive, during a process of increasing the temperature of the nuclear fuel green pellet to a sintering temperature range; and sintering the nuclear fuel green pellet in the sintering temperature range to oxidize the additive to a solid oxide by increasing the oxygen partial pressure in order to suppress volatilization of the additive during the sintering process.