Nuclear-fuel sintered pellets based on oxide in which fine precipitate material is dispersed in circumferential direction and method of manufacturing same

A method of manufacturing an oxide nuclear-fuel sintered pellet in which a plate-type fine precipitate material is dispersed in a circumferential direction, the method comprising:

• mixing an oxide powder, including at least one of a group including uranium (U), plutonium (Pu), gadolinium (Gd), and thorium (Th), with a sintering additive powder, thus manufacturing a mixed powder (first step);
• manufacturing a granulated powder using a sieve after pre-compaction and crushing the mixed powder (second step);
• uniaxially compressing the granulated powder at 300 to 500 MPa, thus manufacturing a nuclear-fuel green pellet (third step);
• performing primary sintering of the manufactured nuclear-fuel green pellet in a hydrogen-containing reducing gas atmosphere at a sintering temperature of about 700 to 1100° C. (fourth step);
• and
• performing secondary sintering in a hydrogen-containing reducing gas atmosphere at a sintering temperature of 1700 to 1800° C. successively after the primary sintering is completed,
• wherein the nuclear-fuel sintered pellet comprises:
• a precipitate material generated due to a sintering additive during a sintering process in a microstructure of nuclear-fuel sintered pellet thereof,
• wherein the precipitate material is uniformly dispersed in a circumferential direction, and wherein the precipitate material forms a donut-shaped two-dimensional precipitate cluster.