Effects of Zr on crystallization kinetics of
Pr-Fe-B amorphous alloys
Pr-Fe-B amorphous alloys
(College of Materials and Chemical Engineering,
Yanshan University, Qinhuangdao 066004, China)
Yanshan University, Qinhuangdao 066004, China)
Abstract: 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 α-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 α-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 α-Fe and Pr2Fe14B in the alloy. The addition of Zr can be used to change the crystallization behavior of the α-Fe phase in Pr-Fe-B amorphous alloy, which is helpful to reduce the grain size for the α-Fe phase.
Key words: Pr-Fe-B amorphous alloys; Zr; crystallization kinetics; activation energy