利用无源效率刻度方法进行建模、效率拟合及伽玛谱分析对稀土精矿、矿渣及最终产品高纯稀土样品的放射性做了调查,结果表明,稀土精矿、矿渣和高纯稀土中均含有放射性核素,但各样品中放射性核素的含量具有明显差异,且铀(钍)系母子体间放射性长期平衡已被破坏。各稀土样品中铀系核素的活度浓度变化范围为33.6 Bq/kg~18322.3 Bq/kg,钍系核素的活度浓度变化范围为4.1 Bq/kg~10442.8 Bq/kg。所有样品中均含有锕系放射性核素,基本处于放射性平衡状态,各样品中核素的活度浓度变化范围最大,为23.8 Bq/kg~25320.2 Bq/kg。对稀土冶炼过程各产品的放射性核素检测分析结果表明,有些生产工艺会去除大部分天然铀系、钍系放射性核素、227Ac以及少量的138La;也有些生产工艺对放射性影响很小;甚至在含量为99.99%的高纯氧化镧产品中依旧含有放射性227Ac和138La,准确地检测可以对生产过程起指导作用。 The radioactivity of rare earth concentrates, slag and high purity rare earth samples of final products were investigated by means of passive efficiency calibration method, efficiency fitting and gamma spectrum analysis. The results showed that rare earth concentrates, slag and high purity rare earth All contained radionuclides, but the content of radionuclides in each sample was significantly different, and the long-term radioactive balance between uranium (thorium) -based parent and child bodies was destroyed. The activity concentrations of uranium-based nuclides varied from 33.6 Bq / kg to 18322.3 Bq / kg for rare-earth samples, and ranged from 4.1 Bq / kg to 10442.8 Bq / kg for thorium-based nuclides. All the samples contained actinide radionuclides, which were basically in a state of radioactive equilibrium. The highest concentration of radionuclides in each sample ranged from 23.8 Bq / kg to 25320.2 Bq / kg. The results of radionuclide detection and analysis of each product in the rare earth smelting process show that some production processes remove most of the natural uranium series, thorium series radionuclides, 227Ac and a small amount of 138La; and some production processes have little effect on radioactivity; Content of 99.99% of high-purity lanthanum oxide products still contain radioactive 227Ac and 138La, accurate detection can play a guiding role in the production process.