Ion induced structural modification and nano-crystalline formation of Zr-Al-Ni-Cu metallic glasses

The effect of the ion implantation on the phase transformation was studied for glassy and crystalline Zr55Al10Ni5Cu30 alloys, using Au+ ions with 500 keV. For the glassy metal surface, nano-crystalline precipitates were effectively formed in the amorphous matrix by 500 keV Au ion irradiation at a fluence of the about 1016 cm−2. On the contrary, the long range ordering in the partly crystalline alloy was lost by the irradiation under the same condition. Moreover, the precipitation during the heat treatment near the crystallizing temperature was effectively suppressed in the ion implanted area. In the irradiated surface, the XPS valence band structure was drastically changed, while shifts of the binding energy were found in the core level electrons of Au 4f and Cu 2p, indicating a strong interaction between the implanted Au atoms and constituent atoms of the Zr-based alloy.