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In the ion beam mixing experiments,eight Fe-Hf-Nb multilayered films,with overall compositions of Fe67Hf22Nb11,Fe67Hf11Nb22,Fe54Hf38Nb8,Fe54Hf30Nb16,Fe54Hf11Nb35,Fe25Hf67Nb8,Fe25Hf50Nb25 and Fe25Hf11Nb64,were irradiated by 200 keV xenon ions to doses ranging from 3×1014 Xe+/cm2 to 7×1015 Xe+/cm2.The results showed that unique amorphous phases were obtained at designed alloy compositions,falling in the favored glass-forming region deduced from three binary metal sub-systems.Interestingly,at some alloy compositions,the crystal-amorphous-crystal transformations were observed back and forth while varying the irradiation doses.In addition,at the alloy composition of Fe25Hf67Nb8,a metastable FCC phase was formed through an HCP-FCC structural phase transformation and it had a large lattice constant identified to be a=4.51 .Besides,the formation mechanism of non-equilibrium alloy phases was also discussed in terms of thermodynamics of solids and atomic collision theory.
In the ion beam mixing experiments, eight Fe-Hf-Nb multilayered films, with overall compositions of Fe67Hf22Nb11, Fe67Hf11Nb22, Fe54Hf38Nb8, Fe54Hf30Nb16, Fe54Hf11Nb35, Fe25Hf67Nb8, Fe25Hf50Nb25 and Fe25Hf11Nb64, were irradiated by 200 keV xenon ions to doses ranging from 3 × 1014 Xe + / cm2 to 7 × 1015 Xe + / cm2. The results showed that unique amorphous phases were obtained at designed alloy compositions, falling in the favored glass-forming region deduced from three binary metal sub-systems. Interestingly, at some alloy compositions, the crystal-amorphous-crystal transformations were observed back and forth while varying the irradiation doses. In addition, at the alloy composition of Fe25Hf67Nb8, a metastable FCC phase was formed through an HCP-FCC structural phase transformation and it had a large lattice constant identified to be a = 4.51 . Besides, the formation mechanism of non-equilibrium alloy phases was also discussed in terms of thermodynamics of solids and atomic collision theory.