Resistance to He2+ induced irradiation damage in metallic glass Zr64Cu17.8Ni10.7Al7.5

This paper used He2+ ion-irradiated metallic glass Zr64Cu17.8Ni10.7Al7.5 and metallic W with an energy of 500 keV at fluences of 2 × 1017, 5 × 1017, 1 × 1018 and 2 × 1018 ions/cm2. Zr-based metallic glass remained mainly amorphous at different fluences. At the irradiation fluence of 2 × 1018 ions/cm2, there was a channel-like damage layer appeared within the range of the surface ions. Cracking and peeling along the grain boundary occurred on the surface of metallic W at the fluence of 1 × 1018 ions/cm2; or even multi-layer peeling occurred at the fluence of 2 × 1018 ions/cm2. TEM analysis revealed that there were a lot of helium bubbles at the end of the range of helium ion. The connection and coalescence growth process of a helium bubble was observed. The surface rms roughness ρrms of Zr-based metallic glass increased first and then decreased with the increase in fluence. The resistance to He2+ irradiation in Zr-based metallic glass was superior to the one in metallic tungsten.