Abstract
Influences of electron beam (EB) irradiation on the impact value for silica glass were studied by using a standard Charpy impact test. EB irradiation below 0.216 MGy, which was one of short-time treatments of dry process at low temperature, increased impact values of the glass. As the EB irradiation generated dangling bonds of the E′ center at the silicon-oxygen atomic pairs in the silica glass, partial relaxation occurred at points of residual strain near dangling bonds in the network structure mainly constructed with silicon-oxygen pairs. If the inter-atomic distance of the silicon-oxygen pairs became to be optimum potential curves of the silica glass, the relaxation should increase the bonding energy of the network structure. Evidently, the increased impact value was mainly due to an increase in the bonding energy for the silicon-oxygen atomic pairs in the atomic network structure, as well as a relaxation of the network structure.
