Electron irradiation-induced structural transformation in metallic glasses

Microstructural evolution of Zr55Cu30Al10Ni5 and Cu50Zr45Ti5 metallic glasses under 200 keV electron irradiation has been studied in situ by transmission electron microscopy. Zr55Cu30Al10Ni5, which has a wider supercooled liquid region, is found to be stable under electron irradiation and no crystallization is observed up to an irradiation fluence of 8.7 × 1026 electrons m−2. In contrast, nanometer size crystalline Cu10Zr7 phases are formed in Cu50Zr45Ti5 under electron irradiation. The partial crystallization is attributed to irradiation enhanced atomic mobility.