Xe离子束辐照硼硅酸盐玻璃和石英玻璃效应对比研究

玻璃固化体作为放射性废物地质处置的第一道安全屏障,它的耐辐照性能研究至关重要.玻璃固化体主要网络结构硅氧四面体与石英玻璃的硅氧四面体是一致的,所以这里用石英玻璃代替玻璃固化体作为研究对象.本文采用Xe离子在相同条件下辐照石英玻璃和硼硅酸盐玻璃.利用纳米压痕技术和椭圆偏振仪表征了辐照前后样品的硬度、模量以及折射率的变化情况.结果表明:硼硅酸盐玻璃和石英玻璃的硬度均随着辐照剂量的增大而减小,硼硅酸盐玻璃的模量随着辐照剂量的增大而减小;石英玻璃的模量随着辐照剂量的增大而增大.模量的变化可能和密度的变化有关,这点与折射率的结果相符.

Comparative studies of irradiation effects in borosilicate glass and fused silica irradiated by energetic Xe ions

As the first safety barrier of high level radioactive waste, the tolerance to radiation of vitrification is critical. Vitrification is a kind of specialized glass used as the package of high-level radioactive waste in nuclear power industry. Because of its structural consistency with the main structure of vitrification (silicon-oxygen tetrahedron), fused silica is used to study the irradiation effect on network of vitrification in the present study. Borosilicate glass, a simplified version of vitrification, is studied under the same conditions for comparison. Hardness values, moduli and refractive indexes of fused silica and borosilicate glass are measured before and after irradiation with nanoindentation technology and elliptic polarization instrument. It is shown in this study that the hardness values of fused silica and borosilicate glass decrease with increasing dose. On the other hand, with dose increasing, the modulus of borosilicate glass decreases but the modulus of silica increases. Change in modulus might be attributed to the change of density, which is consistent with results from the refractive index.