Experience of Beryllium Blocks Operation in the SM and MIR Nuclear Reactors useful for Fusion

摘要

The results are presented concerning the examinations of state of beryllium blocks after the completion of their operation in the SM and MIR reactors. Both cracks and more significant mechanical damages are revealed in the irradiated beryllium blocks. Under neutron irradiation of beryllium radiation degradation of its physical and mechanical properties occurs. It shows itself in embrittlement, decrease of brittle strength level as well in worsening of thermal conductivity that leads to increase of thermal stresses into beryllium block. Under irradiation it takes place damage of beryllium microstructure, in particular, formation of radiation defects occurs in the form of dislocation loops and great amount of helium atoms. Optimization of beryllium radioactive waste storage is related to their preliminary surface and volumetric decontamination.