Effects of Zr on crystallization kinetics of Pr-Fe-B amorphous alloys

The effects of Zr on crystallization kinetics of Pr-Fe-B amorphous alloys have been investigated by DTA and XRD methods. It was found that for Pr8Fe86-xZrxB6(x =0, 1, 2) amorphous alloys, the final crystallized mixture is alpha-Fe and Pr2Fe14B, and the metastable Pr2Fe23B3 Phase occurs during crystallization of Pr8Fe86B6 amorphous alloy, not during crystallization of Pr8Fe86-xZrxB6(x = 1, 2) amorphous alloys. By analyzing the activation energy of crystallization, the formation of an alpha-Fe/Pr2Fe14B composite microstructure with a coarse grain size in annealed Pr8Fe86B6 alloy, is attributed to a difficult nucleation and an easy growth for both the alpha-Fe and Pr2Fe14B in the alloy. The addition of Zr can be used to change the crystallization behavior of the alpha-Fe phase in Pr-Fe-B amorphous alloy, which is helpful to reduce the grain size for the alpha-Fe phase.