Solid state amorphisation of mechanically alloyed Fe-Co-Nb-B alloys

Magnetic and structural characterization of the mechanically alloyed Fe75Si15B10 powders

“…When crystallite size reduces to about 6 nm, a increases by a = 0.5% while c decreases by c = −0.84% with respect to the equilibrium lattice constants for bulk materials. A similar variation tendency of lattice parameters with crystallite size was detected for the Fe 2 B boride nanophase in the mechanically alloyed Fe-Co-Nb-B powder mixture with a = 0.15% and c = −0.18% [26], and in the NC Fe-Mo-Si-B alloy with a = 0.22% and c = −0.24% for a crystallite size of about 25 nm [27]. It has been reported that the lattice cell unit of nanocrystallites will expand with an evident increment of the lattice parameters in intermetallic compounds Ni 3 P and Fe 2 B owing to a supersaturation of vacancies [28].…”

Structural and Thermal Study of Nanocrystalline Fe-Al-B Alloy Prepared by Mechanical Alloying

“…When the crystallite size reduces to about 18 nm, a increases by Da = 0.12 pct, while c decreases by Da = À0.10 pct. A similar variation behavior of lattice parameters with crystallite size was detected for the Fe 2 B boride nanophase in the MA Fe-Co-Nb-B powder mixture with Da = 0.15 pct and Dc = À0.18 pct, [35] in the NC Fe-Mo-Si-B alloy with Da = 0.22 pct and Dc = À0.24 pct for a crystallite size of about 25 nm [36] and in the NC Fe-Si-B powder mixture with Da = 0.5 pct, while c decreases by Dc = À0.84 pct for a crystallite size of about 6 nm. [37] C. Thermal Analysis Alloys synthesized by ball milling usually have disordered structure of the solid solution except for some cases in which the ordered phases can be obtained directly by MA process.…”

“…The latter becomes more significant with smaller crystallites which favor higher solubility of vacancies. [35] The variation of the lattice parameters (a and c) for the Fe 2 B phase is also calculated as a function of milling time and represented in Figure 6(b). The parameters a and c decrease slightly between 4 and 6 hours of milling.…”

The Effect of B and Si Additions on the Structural and Magnetic Behavior of Fe-Co-Ni Alloy Prepared by High-energy Mechanical Milling

“…For example, the solution of point defects in the crystal lattice will disrupt its structure around the vacant positions ultimately leading to a distorted crystal lattice. The latter becomes more significant with smaller crystallites and promotes a higher solubility of the vacancies [23]. On the other hand, it is interesting to note that in the final milling products the lattice parameter increases from the FeCoNi to FeCoNiSi, FeCoNiBamorpous and FeCoNiBcrystalline.…”