Annealing embrittlement of Al89Fe10Zr1 amorphous alloy

The mechanism of annealing embrittlement of A189Fe10Zr1 amorphous alloy is studied. The activation energies for the ductile–brittle transition (Eb) and the precipitation of fcc-Al (Ex) are measured according to Kissinger plot and Arrhenius plot. Their values are Eb=168–l79 kJ mol−1 and Ex=173–204 kJ mol−1, respectively. The correlation between the ductile–brittle transition and the precipitation of fcc-Al means that they are the same thermally activated processes. The analysis of solute concentrations in the alloy using atom probe field ion microscope shows that the precipitation of fcc-Al causes the increase of Fe and Zr concentrations in the residual amorphous phase during the annealing process. This is the main reason for the ductile–brittle transition.