Effect of γ-(Fe,Ni) crystal-size stabilization in Fe–Ni–B amorphous ribbon

Resumo

The effect of stabilizing crystal size in a melt-quenched amorphous Fe₅₀Ni₃₃B₁₇ ribbon is described upon crystallization in a temperature range of 360–400°С. The shape, size, volume fraction, and volume density have been investigated by transmission electron microscopy and X-ray diffraction methods. The formation of an amorphous layer of the Fe₅₀Ni₂₉B₂₁ compound was found by means of atomic-probe tomography at the boundary of the crystallite–amorphous phase. The stabilization of crystal sizes during annealing is due to the formation of a barrier amorphous layer that has a crystallization temperature that exceeds the crystallization temperature of the matrix amorphous alloy.