Kinetic in situ neutron diffraction has been used to study the crystallization of
amorphous Y67Fe33. The results show that partial crystallization first occurs
close to 300 ◦C where the Y phase is formed. The entire sample crystallizes
at 390 ◦C and new Bragg peaks appear, signifying the formation of a novel
Y–Fe phase. This new phase coexists with Y to 450 ◦C when the Bragg peaks
associated with this phase rapidly decrease in intensity and YFe2 also coexisting
with Y, emerges as the final crystallization product. Rietveld refinement
shows that the new phase crystallizes into a hexagonal structure, space group
P63/mmc, with a = 12.8893(7) Å, c = 11.7006(9) Å and γ = 120◦
