Effect of Minor Additions on the Glass Forming Ability of Cu-Based Bulk Metallic Glasses

The effect of minor additions and their content on the glass forming ability (GFA) of Cu55Zr38Al7 bulk metallic glass was studied. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) study show that the GFA of Cu55Zr38Al7 bulk metallic glass is enhanced by 2 at% addition of Ag, Ti, Y or Nd. With 6 at% of Ag addition, the critical size of the metallic glass rod formed is increased from 2 to 4 mm. GFA of Cu55Zr38Al7 bulk metallic glass can also be improved obviously by multiple additions with 2 at% Ag and Y. In conclusion, distinct effect on GFA can be obtained by substitution for chemically similar elements or by enlargement of atom dimension extension in the alloying system.