Effect of Yttrium Doping on Glass-Forming Ability, Thermal Stability, and Corrosion Resistance of Zr50.7Cu28Ni9Al12.3 Bulk Metallic Glass

Metallic glasses (MGs) possess excellent corrosion resistance due to their amorphous nature. Zr-Cu-Ni-Al is one of the most investigated metallic glass (MG) systems due to its excellent corrosion resistance, relatively low cost, and nontoxic qualities. Yet the application of the Zr-Cu-Ni-Al MGs is still limited by its glass forming ability (GFA). It has been found that the doping of yttrium can purify the Zr-Cu-Ni-Al melt and increase GFA. However, research on the yttrium doping's corrosion resistance is still lacking. In the present work, (Zr50.7Cu28Ni9Al12.3)(100-x)Y-x (x = 0 (Y0), 1 (Y1), 2 (Y2), 3 (Y3)) alloys were prepared, and the effects of the yttrium doping on the thermodynamic parameters, crystallization activation energy, and corrosion resistance were studied. It was found that the doping of yttrium can improve the GFA and the crystallization-activation energy of the Zr50.7Cu28Ni9Al12.3 MG. The largest GFA is obtained when the yttrium-doping content reaches 2 at.%. The parameter gamma is found to be most suitable for the GFA evaluation of the (Zr50.7Cu28Ni9Al12.3)(100-x)Y-x alloy system. Y2 alloy exhibits the best corrosion resistance among the Y0-Y3 alloys according to the potentiodynamic polarization results. The simultaneous increase of the GFA, thermal stability, and corrosion resistance was achieved in the Zr50.7Cu28Ni9Al12.3 MG by proper yttrium doping.