Laser patterning of Fe–Si–B amorphous ribbons in magnetic field

Dynamic crystallization during non-isothermal laser treatment of Fe–Si–B metallic glass

“…Such a microstructure has been reported to improve magnetic performance of partially crystallized Fe-Si-B metallic glass by resulting in improved saturation magnetization and reduced coercivity (Table 2.1) [1,27,43,44,71,94]. Furthermore, it was also pointed out that magnetostrictive effects (the undesired changes in shape of a magnetic material upon undergoing the process of magnetization [95]) would be minimized in such a partially crystallized Fe-Si-B metallic glass because the magnetostrictive vectors of crystalline and amorphous phases have opposite directions [96].…”

“…These metallic alloys solidified amorphous are called metallic glasses. Owing to disordered/amorphous structure, metallic glasses posses unique set of properties including very high strength, good corrosion resistance as a result of absence of grain boundaries, excellent soft magnetic properties, high hardness and wear resistance [1,4,12,22,[42][43][44][45][46][47]. As an example, the strength of metallic glasses is much higher than conventional materials like high strength steels (Fig.…”

“…However, in case of amorphous material system, it is reasonable to take value of X 0 as zero [69], hence the expression in Eq. Although conventional isothermal or near isothermal heating (annealing) is a feasible method of inducing crystallization followed by nano/micro grain growth in amorphous phase and is as flash annealing [28], microwave heating [29], and laser processing [1,30,43,71]. Flash annealing consists of holding the material at constant high temperature (static heating) in a furnace for short amount of time on the order of few seconds, followed by rapid quenching.…”

“…The latter results in a measurable plastic deformation independent of the loading direction. Thus, even though crystallization may be necessary for improving functional properties such as soft magnetic properties in case of Fe based metallic glass [1,27,30,43,71] the microstructural investigation and control becomes critical to ensure mechanically reliable performance. On the other hand, as stated earlier, crystallization can serve as the barrier to shear band movements and further nucleate new shear bands leading to macroscopic plasticity in metallic glasses [6,25].…”

Crystallization Mechanism in Spark Plasma Sintered Bulk Metallic Glass Analyzed using Small Angle Neutron Scattering

“…Melt spun metallic glass ribbons in the Fe-Si-B alloy system also possess high permeability and low core loss of about one-third that of grade M3 electrical steel. Metglas R 2605SA1 ribbons exhibit saturation induction of 1.56 T and a maximum dc permeability of 600 kNA −2 [13][14][15] . These properties, combined with the fact that iron based metallic glasses are significantly cheaper than other Zr or Pd based metallic glasses, have made these materials extremely versatile.…”