Magnetic pulsed compaction of ferromagnetic nano-powders for soft-magnetic core

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 449; pp. 401 - 406
• Main Authors: Hong, S.J., Lee, G.H., Rhee, C.K., Kim, W.W., Lee, K.S.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-03-2007; Elsevier
• Subjects: Applied sciences; Catalytic effect; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Cu 2O (cuprite); Exact sciences and technology; Hydrolysis; Magnetic properties and materials; Magnetic properties of nanostructures; Materials science; Metal powders; Metals. Metallurgy; Nano cube; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Physics; Powder metallurgy. Composite materials; Production techniques; Hydrolysis; Catalytic effect; Cu 2O (cuprite); Nano cube; Scanning electron microscopy; Particle size; Powders; Annealing; Densification; Magnetic field effects; Iron alloys; Magnetically soft alloy; Soft magnetic materials; Powder metallurgy; Cu2O (cuprite); Compacting; Silicon alloys; Magnetic permeability; Pulsed field; Microstructure; Nanocrystal
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.02.401

Densification of nanocrystalline Fe–6.5
wt.% Si powder with 20–40
μm particle size by uniaxial compaction and magnetic pulsed compaction was investigated in the temperature range of 23–400
°C and applied pressure range of 0.3–2.0
GPa. The microstructure of mechanically milled powder for 36
h showed a distribution of α-Fe phase 13–30
nm in size embedded in the matrix. The maximum relative density of Fe–6.5
wt.% Si green compact (core) was achieved more than 82%, by magnetic pulsed compaction (MPC) at room temperature under 2.0
GPa using annealed coarse powder (milled for 4
h), while it was less than 62% by a uniaxial static compaction. Finally, a remarkable effect of the compaction using the MPC process on the final density of Fe–Si alloy was measured in this research. The magnetic permeability of Fe–6.5
wt.% Si and Fe–6
wt.% Al–9
wt.% Si core is increased with the relative density increased.