Effect of copper addition on the glass forming ability of a Fe-Co based alloy

The effect of copper addition on the glass forming ability of Fe36Co36Nb4Si4.8B19.2 bulk metallic glass is studied. With 0.6 at% of copper addition, the critical size of the glassy rod formed is enlarged from 2 to 4 mm. Differential scanning calorimetry (DSC) study shows that the copper addition depressed the phase separation before the eutectic transformation upon cooling. And the crystallization of the alloy with copper addition is carried through three stages upon heating. Energy dispersive spectroscopy study shows that the copper addition reduces the oxygen content of the alloy.