Real-Time Neutron Diffraction Study of Crystallization Kinetics in Amorphous Fe₇₈B₁₃Si₉ Alloy

Abstract

The transformation from the as-quenched amorphous to the crystalline state in Fe₇₈B₁₃Si₉ alloy has been investigated using a new-type neutron diffractometer. The time resolved diffraction patterns clearly show that this alloy crystallizes into FeSi alloy and Fe₂B in that order. The time evolution of these crystalline phases can be analyzed by the Kolmogorov-Johnson-Mehl-Avrami equation with the exponent of about 2.5 over a wide temperature range. This suggests that the crystallization occurs by the diffusion-controlled growth with a constant nucleation rate. The scaling behavior in the crystallization kinetics is also discussed.