Metal treatment – Process of modifying or maintaining internal physical... – Treating loose metal powder – particle or flake
Reexamination Certificate
2006-03-13
2009-10-27
Wyszomierski, George (Department: 1793)
Metal treatment
Process of modifying or maintaining internal physical...
Treating loose metal powder, particle or flake
C148S105000, C148S121000
Reexamination Certificate
active
07608158
ABSTRACT:
The present invention includes particle compositions and methods of fabrication that prevent agglomeration, thereby maintaining particle size and/or shape. Particles of the present invention were prepared after embedding chemically disordered metal-containing particles in at least one salt to form a dispersion. The dispersion of particles in salt was treated to temperatures of at least about 500 degrees Centigrade for several hours. Particles were easily recovered from the dispersion and did not agglomerate. The particles were also absent contaminating salts after performing simple washing and/or rinsing steps. Structural, compositional and/or magnetic characterizations of the metal-containing particles confirmed that they had not agglomerated. When particles with an fcc structure formed a dispersion with at least one salt, the method yielded the formation of particles having an fct structure with high magnetic anisotropy and without a substantial change in size and/or shape. When desired, however, particles shape and/or size may be changed.
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Board of Regents the University of Texas System
Paredes J. Peter
Rosenbaum & Silvert, P.C.
Shevin Mark L
Wyszomierski George
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