核级碳化硼环状制品热压烧结工艺与性能研究  

Study on the Hot-Pressing Sintering Technology and Properties of Nuclear Class Boron Carbide Ring Products

作　　者：郭志家[1] 杨历军[1] 刘天才[1] 范月容[1] 王亚婷 赵守智[1] 柯国土[1] 彭朝晖[1] GUO Zhijia;YANG Lijun;LIU Tiancai;FAN Yuerong;WANG Yating;ZHAO Shouzhi;KE Guotu;PENG Zhaohui(China Institute of Atomic Energy,P.O.Box 275-98,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《核科学与工程》2022年第4期968-974,共7页Nuclear Science and Engineering

摘　　要：本文以核级碳化硼粉末为原料,按照烧结环状制品密度(2.15±0.05)g/cm^(3)(约90%T.D.)为设计基准,开展TOPAZⅡ型空间核动力装置碳化硼环状制品的热压烧结工艺及其组织与性能研究。试验结果表明,采用温度2 150℃、压力20 MPa、保温保压1 h的热压烧结工艺,可制备出满足设计密度要求的碳化硼环状制品,制品B丰度>85%,平均晶粒尺寸小于15μm,气孔尺寸小于5μm。在室温~620℃温度范围内,随着试验温度的升高,物理和力学性能呈现不同规律的变化,线膨胀系数逐渐增大,热导率逐渐降低,抗弯强度和抗压强度也逐渐降低,上述实测试验数据可作为TOPAZⅡ空间核动力装置在各种运行工况下,碳化硼环状制品是否能保证结构完整性和性能稳定性的参考依据。In this paper, according to the density of the sintered ring products(2.15±0.05g/cm^(3),about 90%T.D.) as the design benchmark,the hot pressing process, and the microstructure and properties of boron carbide ring products for TOPAZⅡ space nuclear power plant use nuclear-class boron carbide as raw material were studied. The experimental results showed that the boron carbide ring products prepared by the hot pressing condition of 2150 ℃ and 20MPa for one hour can meet the design density requirements. The abundance of ring products are more than 85%, the average grain size is less than 15 μm and the pore size is less than 5 μm.In the room temperature range to 620℃, with the increase of test temperature, the physical properties and mechanical properties showed different trends, linear expansion coefficient increases gradually, thermal conductivity reduces gradually and bending strength, and compression strength reduce gradually. All the measured data can be used as a reference whether boron carbide ring products can guarantee the structural integrity and performance stability under various operating conditions of TOPAZⅡ space nuclear power plant.

关 键 词：碳化硼 丰度 热压烧结 密度 性能 

分 类 号：TL345[核科学技术—核技术及应用] TF123[冶金工程—粉末冶金]