高温烧结二氧化钍芯块技术研究  

Study of High Temperature Sintering Technology for ThO_2 Pellet

作　　者：陈连重 任永岗[1] 李爱军[1] 杜继军[1] 郭洪[1] 

机构地区：[1]中核北方核燃料元件有限公司,内蒙古包头014035

出　　处：《原子能科学技术》2015年第B05期438-442,共5页Atomic Energy Science and Technology

基　　金：内蒙古自治区科技创新引导资金资助项目(20101703)

摘　　要：为制备满足重水堆核燃料技术要求的二氧化钍芯块,以用草酸沉淀法制得的二氧化钍粉末为原料,采用造粒、模压、高温烧结工艺开展了芯块制备技术研究。分析研究了粉末比表面积、模压、烧结工艺对二氧化钍芯块晶粒尺寸、密度的影响。结果表明:粉末的比表面积、成型压力、烧结温度是影响芯块密度最主要的因素;较高的二氧化钍粉末比表面积不但提高了芯块的烧结动力,也提高了晶粒长大的驱动力,晶粒尺寸较大;在真空或氩气气氛中,及较高的烧结温度下,可制得密度和晶粒尺寸满足重水堆燃料指标要求的二氧化钍芯块。For the preparation of ThO2 pellet meeting to heavy water reactor （HWR） fuel element technical requirements, ThO2 powder made by oxalic acid precipitation process was used as raw material. The ThO2 pellet was prepared through the granulating, pressing and sintering process. The effects of granulating, pressing and sintering process on the grain size and density were analyzed. The results indicate that the specific surface area of powder, press force and sintering temperature are the main effect factors of pellet density. The driving forces of ThO2 pellet sintering and grain growth increase with specific surface area of ThO2 powder, and the ThO2 pellet with larger grain size can be acquired by using the higher specific surface area of ThO2 powder. The ThO2 pellet which can meet the HWR fuel element technical requirements of density and grain size can be prepared under the vacuum or argon atmosphere and high sintering temperature.

关 键 词：二氧化钍 烧结 密度 晶粒尺寸 

分 类 号：TL245[核科学技术—核燃料循环与材料]