Abstract
This study addresses the consequences of three irradiation scenarios on the structure and macroscopic properties of the ISG glass. The coupling effect between 2.5 MeV electron irradiation (simulating the effects of beta particles and gamma rays) and 7 MeV Au irradiation (simulating the nuclear collisions of the recoil nuclei of alpha decays) was studied by comparing two monobeam irradiations with a sequential double beam irradiation. Various experimental techniques were used to characterize the glass structure and properties, combining Raman, NMR, IR-ATR spectroscopies, hydrostatic weighing, He pycnometry, X-Ray Reflectivity, AFM, surface tension and Vickers microhardness measurements. Electron irradiation up to 3.25 GGy induces only small changes of ISG glass structure and macroscopic properties than Au irradiation. Moreover, the magnitude of the changes induced by the sequential irradiation scenario, i.e. electron followed by Au ions, are the same as the one induced by the monobeam irradiation by Au ions, except for the surface tension. Because the bulk damage state are similar, this work demonstrates that there is no coupling between the damage generated by the electron irradiation and the subsequent nuclear collision generated by Au ions. Finally, the hardness and density changes of ISG glass are very similar to those of SON68 glass when submitted to similar irradiation conditions by electron or nuclear collisions. Therefore ISG glass is found to be a good glass surrogate with respect to radiation ageing of the SON68 glass.