【摘要】 Gd₂O₃-UO₂可燃毒物燃料芯块的烧结密度是个重要指标,是质量控制的主要项目之一。为此研究了Gd₂O₃粉末预处理、添加剂、混合方式和时间、烧结气氛、烧结温度和时间等工艺参数对Gd₂O₃质量百分含量分别为0,3％,7％,10％的Gd₂O₃-UO₂芯块最终密度的影响。结果指出:预处理有利于Gd₂O₃分布均匀;添加草酸铵能有效地调整芯块密度;烧结温度1750℃为宜。选用了合适的工艺参数,制备出了密度为理论密度的93.5％～96.5％,且均匀性和微观结构等均满足设计要求的辐照考验用Gd₂O₃-UO₂芯块。更多还原

【Abstract】 The sintered density of Gd2O3-UO2 burnable poison fuel pellets is an important quality index and is one of main QC items. Therefore, the efforts were made to investigate the factors affecting the sintered density of Gd2O3-UO2,that is, the influences of pre-treatment of Gd2O3 powder, additives, mixing methods and time, sintering atmosphere, sintering temperature and time on the final density of Gd2O3-UO2 pellets contained 0, 3% , 7% , and 10% (mass percentage) Gd2O3. The results show: the pre-treatment is useful for improving the distribution of Gd2O3; the additive of ammonium oxalate will effectively adjust the density of pellets; 1750C is the suitable sintering temperature. The proper process parameters have been obtained, and the Gd2O3-UO2 pellets prepared for in-pile irradiation test meet the design requirements for the density (93. 5%-96-5% of T. D. ), homogeneity, microstruc-ture, etc.更多还原