核反应堆用碳化硼芯块常压烧结工艺研究  

Study on pressless sintering of B_4C pellets used in nuclear reactors

作　　者：李圆圆[1,2] 刘海[1] 李统业[1,2] 杨静[1] 潘小强[1,2] 张雨 

机构地区：[1]中国核动力研究设计院,成都610041 [2]核燃料及材料国家重点实验室,成都610041

出　　处：《粉末冶金技术》2017年第1期53-56,67,共5页Powder Metallurgy Technology

摘　　要：以核级碳化硼粉为原料,酚醛树脂作粘结剂与助烧剂,用钢模成形方法制备出碳化硼生坯,在碳管炉中用常压烧结方法在2250℃保温40 min,制备出高温气冷堆控制棒用碳化硼环形芯块。用化学分析方法分析了原料粉与碳化硼烧结体的化学成分,用排水法对芯块的密度进行测试,研究了碳质量分数对碳化硼芯块密度的影响,用扫描电镜对生坯与芯块的微观结构进行研究,对1:1大尺寸碳化硼芯块的变形量进行统计。结果表明:碳对碳化硼具有很好的助烧作用,碳化硼的密度随碳含量的增加而增加,当碳质量分数为5%时,最高密度达到2.35 g/cm^3;碳掺量为3%时,制得的1:1碳化硼芯块的密度为2.0 g/cm^3,化学成分等各项指标均满足反应堆用核级碳化硼芯块的技术条件要求。By using the high pure B4C powder as the starting material and the phenol-formaldehyde resin as the sintering aids and binders, the B4C pellets were prepared by die pressing and then held at 2250 ℃ for 40 min. The chemical components of raw powder and pellets were analyzed by chemical analytical methods, the densities of pellets were characterized by Archimedes method, the microstructures of pellets were observed by scanning electron microscopy （SEM）, and the deformation of the B4C annual pellets were investigated and summarized. The results show that carbon has the remarkable effect on the densification of B4C pellets, the density of B4C pellets increases significantly with increasing carbon content, the maximum value of 2.35 g/cm3 is obtained at the carbon content of 5wt%, and B4C pellets with the sintered density of 2.0 g/cm3 is obtained by adding 3wt% carbon. The chemical content and other technical indexes can meet the requirement of the B4C pellets used in nuclear reactors.

关 键 词：碳化硼 常压烧结 控制棒 核反应堆 

分 类 号：TF121[冶金工程—粉末冶金]