Radiation damage in silicate glass

Previous investigations of the response of complex waste-storage glasses to high-energy electrons has shown that the glass decomposes, sometimes with the formation of gas-filled bubbles. Further investigations in this work on the behavior of binary alkali silicate glasses have shown a similar response, but furthermore the damage microstructures are related to the cation diffusivities. The electron-damage results have also been correlated with gamma and ion irradiations. Gamma irradiation will also induce the bubbles, and a quantification of the damage shows it to be a significantly more-efficient process than from electron induction. The ion irradiations showed similar damage, which arises only from the electronic component of the stopping. The efficiency of this process is intermediate between that of the gamma and the electron responses. An overall comparison of the nuclear and electronic energy depositions for the various irradiations shows the importance of electronic processes and the relative ineffectiveness of nuclear ones in inducing the glass decomposition. The decomposition of the glass in this way is strongly dose-rate dependent, with lower dose rates more efficiently inducing the damage. This observation is critical to the use of silicate glasses as nuclear-waste containment media, and reveals that the decomposition of defense-waste glasses in this way must also be considered