Enhancement of corrosion resistance in bulk metallic glass by ion implantation

In this paper, ion-implantation technique was applied to improve corrosion resistance of a newly developed La-based bulk metallic glass with poor corrosion resistance. It is found that the alloys after ion implantation with doses ranging 6 × 1016-1 × 1017 Nb/cm2 have a remarkable enhancement of corrosion resistance in chloride containing environments and acid solution with respect to the alloy without the surface treatment while the implanted alloys still have high glass forming ability. The improvement of corrosion resistance for the implanted alloys is attributed to the high passivating ability of the Nb-containing surface layer. These results obtained here clearly demonstrate that the ion-implantation technique could be a useful method to improve the corrosion resistance of bulk metallic glasses without losing glass forming ability of alloys.