Abstract
The effects of heat treatment on the microstructures, crystallization kinetics, mechanical performance, and anti-corrosion behavior of a hypoeutectic Zr68Al8Ni8Cu16 bulk metallic glass (BMG) were studied. Through annealing, the precipitated phases were crystalline Zr2Cu and Zr2Ni. The total crystallinity was determined to be 10% and 77% for the samples annealed at 673 K and 713 K, respectively. The partial crystallization of the alloy leads to a dramatic deterioration in the ductility as compared to the as-cast BMG. Furthermore, the decrease in the ductility was accompanied by an increase in the crystallinity. The as-cast Zr-based BMG exhibited a greater corrosion resistance in the HCl solution than that of the annealed alloy. The depletion in the Zr and Al cation fractions of the surface oxidation film, which resulted from the precipitation of reactive nanocrystalline phases from the glassy matrix, is responsible for the reduced corrosion resistance.
