PENGARUH DISTRIBUSI UKURAN SERBUK UO2 PENGAYAAN 2%–5% PADA DENSITAS PELET UO2

Abstract

A study of UO₂ pellet fabrication using 2%, 3%, 4% and 5% enriched UO₂ powder without conditioning has been carried out. There is no published research on the relationship between UO₂ powder size distribution and UO₂ pellet density in the range of powder sizes studied in this work. Therefore, through this research the influence of size distribution and weight fraction of UO₂ powder on various densities was studied to obtain UO₂ sintered pellet with a density that meets the requirements as PWR fuel. UO₂ pellets were fabricated through cold compaction with variation in pressure of 2, 3 and 4 ton/cm2 and sintering process at 1700 °C for 3 hours. Each UO₂ feed powder with its size distribution and weight fraction was directly fabricated into pellets without conditioning.The powder sieving process shows that the 2% and 4% enriched UO₂ powders have a monomodal powder size distribution while the 3% and 5% enriched UO₂ powders are trimodal size. The green pellets density of 2%, 3%, 4% and 5% enriched UO₂ powders are 54.3%TD, 53.19%TD, 52.45%TD and 52.33%TD respectively. The density of sintered pellets from 2% and 5% enriched UO₂ powders are 91.13-91.70%TD and 75.33-77.57%TD. The sintered pellets of 3% and 4% enriched UO₂ powders were cracked or broken so that the density could not be measured. Based on the pellet density data, it is concluded that the 2% enriched UO₂ powders with monomodal size distribution that are dominated by fine powder smaller than 75µm has better compaction capability and sintering ability than other UO₂ powders. This research needs to be continued to determine the proper size distribution of the UO₂ powder and its weight fraction as compaction process feed in order to obtain higher sintered pellets density that meet the requirements of PWR fuel.