高温气冷堆，是四代核反应堆堆型之一，具有良好的固有安全性，得到了广泛的研究与关注。HTR-10在初装堆时会装入大约一半的石墨球。在HTR-10运行过程中，石墨球会因受到辐照，并与燃料球、堆芯构件、管道和设备等产生磨蚀作用而含有一定的放射性裂变产物和活化产物。本课题对HTR-10辐照后石墨球放射性核素进行分析，将为高温气冷堆核电厂源项分析、职业照射评估提供重要参考依据，为放射性废物最小化和退役方案的制定提供有力的技术基础。石墨球的碳元素以及所含的杂质在堆芯内经中子长时间照射后，会产生放射性核素。本课题对辐照石墨球进行石墨芯柱钻取、锉取石墨粉末样品、测量、燃烧、滴定等操作过程，测量分析核素在径向的分布情况。本课题还对HTR-10辐照石墨球内关键核素的来源进行分析。并将辐照石墨球放射性核素的实验测量值与理论计算值进行比对。本课题研究表明：（1）HTR-10辐照石墨球中的关键核素含有H-3、C-14、Co-60、Cs-137，部分辐照石墨球有Eu-152、Eu-154大量存在; （2）H-3、C-14、Co-60、Cs-137、Eu-152、Eu-154的比活度相对于石墨球样品的中心呈现对称分布;（3）石墨球样品中C-14、Cs-137、Eu-152、Eu-154的比活度几乎均匀分布; （4）H-3、Co-60的表面比活度显著高于石墨球内比活度。对本课题的实验和理论结果分析表明，HTR-10辐照石墨球中活化靶核素除了来源于石墨材料本身所含杂质外，因石墨球与金属部件相互磨蚀而带入堆芯内的杂质也是不可忽略的靶核素来源，特别是对于Co-60的产生。

The high temperature gas-cooled reactor, as one of the Generation Ⅳ reactors, has been widely studied and concerned for the excellent inherent safety. In core of the HTR-10 reactor, the graphite pebbles will be due to the characteristics of the heap, running history, neutron flux, trajectory, residence time and other factors, which bring about significantly different irradiation. This paper is the analysis of the radionuclides of the irradiated graphite pebbles in HTR-10, which will provide an important reference for the source terms analysis、the occupational exposure assessment、the radioactive waste minimization and the decommissioning technical foundation.Due to the graphite itself and the impurities contained irradiated by neutron flux in the core, will produce radioactive nuclides. The radial distribution of these nuclides is measured by drilling the graphite core of the graphite pebble、tapping the sample of graphite powder、instrument measurement、burning and titration. In this paper, the experimental measurements of the radionuclide are compared with the estimates of the specific activity of the model.The results show that: (1) The key radionuclides in the irradiated graphite pebbles contain H-3、C-14、Co-60、Cs-137, and some of the irradiated graphite pebbles are Eu-152 and Eu-154; (2) The specific activity of H-3、C-14、Co-60、Cs-137、Eu-152、Eu-154 exhibites a symmetrical distribution relative to the center of the graphite pebble; (3) The specific activity of C-14、Cs-137、Eu-152、Eu-154is almost uniformly distributed in the irradiated graphite pebbles; (4)The surface specific activity of H-3、Co-60 is significantly higher than the internal specific activity of the graphite pebbles.The experimental and theoretical results show that the activated target radionuclides are produced not only by graphite material itself, but also by the abrasiver brought into the core from the graphite pebbles and the metal parts which is are not ignored, especially for Co-60.