A study on nanocrystallization of alloy Fe73Cu1Nb1.5V2Si13.5B9 by high-energy ball milling

In order to lower the price of Finemet alloy, a new nanocrystalline alloy was developed, in which Nb was partly replaced by V. This paper focused on the study of its nanocrystallization induced by high-energy ball milling. It was shown that after milling for 3 h or so, uniformly distributed nanocrystalline phase α-Fe(Si, B, V, Nb, Cu) began to form. The milling time required for the nanocrystallization of the amorphous alloy upon ball milling depended very much on milling intensity. The higher the intensity, the shorter the milling time. After full crystallization a complex solid solution α-Fe(Si, B, V, Nb, Cu) was obtained. The crystallization process is polymorphous and not primarily observed during conventional thermal annealing. The kinetics of the mechanically induced crystallization of amorphous Fe73Cu1Nb1.5V2Si13B9 alloy may be described by JMA model. The value of Avrami exponent n was 1.53, implying a zero-nucleation rate and crystals growth in all shapes from very small dimensions; the intrinsic factors of controlling the mechanically induced crystallization of the amorphous alloy Fe73Cu1Nb1.5V2Si13B9 may be the deformation and local temperature rise.