Abstract
It has been demonstrated for the first time that severe plastic deformation (SPD) permits to produce the metallic alloys containing two coexisting amorphous phases from the crystalline multiphase alloy. The as-cast Ni₆₀Nb₁₈Y₂₂ alloy was coarse-grained and contained mainly NiY phase (grain size 25 μm) and also NbNi₃, Ni₂Y, Ni₇Y₂ and Ni₃Y phases (grain size 3-5 μm). High pressure torsion (4 GPa, 10 torsions) completely changed the structure. The sample after SPD contained two glassy phases and two other nanocrystalline NiY and Nb₁₅Ni₂ phases (grain size about 20 nm). The coarse-grained alloy was mainly ferromagnetic with a small paramagnetic component. After SPD the alloy becomes strongly diamagnetic with a small ferromagnetic component. Therefore, it has been revealed that severe plastic deformation allows one to produce the composite amorphous alloys.

Key words
severe plastic deformation, Y-Ni-Nb alloys, amorphous phases

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