METHOD OF MANUFACTURING NUCLEAR FUEL PELLET CONSISTING OF DUPLEX GRAINS

• Main Authors: KIM JAE IK, NA YEON SOO, LIM KWANG YOUNG, JUNG TAE SIK, GO DAE GYUN, LEE SUNG JAE, JANG HUN, YOO JONG SUNG, KIM YOON HO, CHOI MIN YOUNG, LEE CHUNG YONG, MOK YONG KYOON, LEE SUNG YONG
• Format: Patent
• Language: English; Korean
• Published: 14.03.2018
• Subjects: CHEMISTRY; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; INORGANIC CHEMISTRY; METALLURGY; NUCLEAR ENGINEERING; NUCLEAR PHYSICS; NUCLEAR REACTORS; PHYSICS

The present invention relates to a method for manufacturing a nuclear fuel pellet with a duplex grain tissue, and more particularly, to a method for manufacturing a uranium oxide pellet with a duplex grain tissue in which the grain size of the outer region of the pellet is larger than the grain size of the inner region of the pellet by forming an additive and a liquid phase in a molded body by infiltrating a compound including a silicon element or silicon oxide into the outside of the molded body without using a dual structure forming method. According to the present invention, the safety and burn-up of a nuclear fuel can be greatly enhanced in high burn-up by mitigating a mechanical interaction between a coating tube and the pellet and suppressing the formation of a rim structure through the functional interaction of the grain by providing the nuclear fuel pellet with the duplex grain tissue in which the inner side and the outer side are different from each other, and can increase an operation output and an operation temperature. 본 발명은 이중결정립 조직을 갖는 핵연료 소결체의 제조방법에 관한 것으로서, 이중구조 성형방법을 사용하지 않고 실리콘 원소 또는 실리콘 산화물을 포함하는 화합물을 성형체 외부에 침투시켜 성형체내의 첨가제와 액상을 형성시킴으로써 소결체 외부영역의 결정립 크기가 내부영역의 결정립 크기보다 큰 이중결정립 조직을 갖는 우라늄산화물 소결체 제조방법을 제공하는데 있다. 상기와 같은 본 발명에 따르면, 외·내부가 다른 이중결정립 조직을 갖는 핵연료 소결체를 제공함으로써 결정립의 기능적 상호 작용을 통하여, 림 구조(rim structure) 형성의 억제와 소결체와 피복관의 기계적 상호작용을 완화시켜 고연소도에서의 핵연료의 안전성 및 연소도를 크게 증진시키며, 운전 출력 및 운전 온도를 높일 수 있다.