Influence of Plastic Deformation on Nanocrystallization of Finemet Alloy

Abstract

The Finemet alloy prepared by the crystallization of an amorphous precursor is a basic model material for study of magnetic nanoparticle structures. Intensive plastic deformation localized in adiabatic shear bands causes the intensive heating and structural changes in the amorphous alloy. These changes influence the magnetic properties of the amorphous precursor for the Finemet crystallization.

Influence of Plastic Deformation on Devitrification of Fe_{73.5}Nb_{3}Cu_{1}Si_{13.5}B_{9} Amorphous Alloy

“…The shallow pits are formed via the creation of radial and tangential shear bands. Repeating of impactions leads to creation of more complex crosslinked shear band morphology [7,8]. Application of the modulated magnetic eld during the thermogravimetry enables to separate the buoyancy and the sample mass stability problems.…”

Can Severe Plastic Deformation Tune Nanocrystallization in Fe-Based Metallic Glasses?

“…Because of the very high hardness of the Vitroperm alloy Fe 73.9 Cu 1 Nb 3 Si 15.5 B 6.6 (6–10 GPa) and particularly of Makino’s alloy Fe 81.2 Co 4 Si 0.5 B 9.5 P 4 Cu 0.8 (up to 16 GPa at least when fully crystallized), the feature of SPD methods utilizing high hydrostatic pressures up to about 10 GPa seems essential to provide any plastic deformation in these alloys (e.g., [ 5 , 24 , 25 , 26 ]). So far, some amount of deformation has been achieved by ball milling [ 27 ], impact hammering [ 28 ]) and HPT (e.g., [ 14 , 29 , 30 , 31 ]) but these efforts were so far limited to very small samples. However, SPD methods are basically bottom-up methods to achieve bulk nanocrystalline and/or amorphous metals and alloys, they are not only capable of nanocrystallization but can even realize massive materials from amorphous ribbons (e.g., [ 15 ]).…”