Browsing Department of Physics by Subject "Nanoparticles"
Now showing items 1-17 of 17
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Anisotropic nanostructured magnets by magnetic-field-assisted processing
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2010-04-15)It has been a great challenge to produce anisotropic nanocrystalline bulk magnets. In this paper, we report our recent work in preparing anisotropic bonded magnets consisting of SmCo5 nanocrystalline particles. The work ... -
Bimagnetic nanoparticles with enhanced exchange coupling and energy products
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2009-01-06)Bimagnetic FePt/Fe3O4 nanoparticles with core/shell or heterodimer structure have been prepared using a sequential synthetic method. The dimension of both FePt and Fe3O4 was tuned by varying the synthesis parameters. The ... -
Bulk FePt-based nanocomposite magnets with enhanced exchange coupling
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2007-07-23)High density bulk FePt/Fe3Pt nanocomposite magnets have been prepared by high-pressure warm compaction of chemically synthesized FePt and Fe3O4 nanoparticles. It is found that the density increases with the compaction ... -
Bulk FePt-based nanocomposite magnets with enhanced exchange coupling
(AIP, 2007)High density bulk FePt/Fe3Pt nanocomposite magnets have been prepared by high-pressure warm compaction of chemically synthesized FePt and Fe3O4 nanoparticles. It is found that the density increases with the compaction ... -
Curie temperatures of annealed FePt nanoparticle systems
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2007-03-28)The chemically synthesized FexPt100-x nanoparticles with controlled compositions were annealed to transfer the disordered face-centered-cubic structure to the ordered structure. It was found that the L10 FePt structure can ... -
Do thermal fluctuations influence the recoil loops of nanocomposite magnets?
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2008-07-11)An exchange-coupled FePt/Fe3Pt nanocomposite system with well defined hard/soft two-phase morphology was prepared by reducing chemically synthesized FePt/Fe3O4 bimagnetic nanoparticles. It was interesting to observe that ... -
Effect of thermal fluctuations on the recoil loops of SmCo5[subscript]/Fe nanocomposite system
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2009-02-13)The correlation between the recoil loop openness and the activation volume has been studied for the SmCo5/α-Fe nanocomposite powder material prepared by mechanical alloying. The α-Fe phase content in the nanocomposite ... -
Effects of particle size and composition on coercivity of Sm–Co nanoparticles prepared by surfactant-assisted ball milling
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2010-04-15)The correlation between the recoil loop openness and the activation volume has been studied for the SmCo5/α-Fe nanocomposite powder material prepared by mechanical alloying. The α-Fe phase content in the nanocomposite ... -
High thermal stability of carbon-coated L10-FePt nanoparticles prepared by salt-matrix annealing
(AIP, 2008)Monodisperse L10-FePt nanoparticles with size ranging from 3 to 8 nm were prepared by the salt-matrix annealing method. It was observed that the annealed particles have high thermal stability—no sintering occurred even ... -
High thermal stability of carbon-coated L1[subscript]0-FePt nanoparticles prepared by salt-matrix annealing
(Institute of Applied PhysicsDepartment of Physics, The University of Texas at Arlington, 2008-02-08)Monodisperse L10-FePt nanoparticles with size ranging from 3 to 8 nm were prepared by the salt-matrix annealing method. It was observed that the annealed particles have high thermal stability—no sintering occurred even ... -
Microstructures and magnetic alignment of L10 FePt nanoparticles
(AIP, 2009)Chemically ordered FePt nanoparticles were obtained by high temperature annealing a mixture of FePt particles with NaCl. After the NaCl was removed with de-ionized water, the transformed FePt nanoparticles were redispersed ... -
Observation of L1[subscript]0-like chemical ordering in a decahedral FePt nanoparticle by C[subscript]s-corrected high resolution transmission electron microscopy
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2009-03-09)The state of the chemical ordering in a decahedral FePt nanoparticle was studied using aberration corrected high resolution transmission electron microscopy. With the reduced image delocalization effect as a result of ... -
Phase Transformation and Magnetic Hardening in Isolated FePt Nanoparticles
(IEEEDepartment of Physics, The University of Texas at Arlington, 2009-03-31)Isolated monodisperse L1[subscript]0 FePt nanoparticles coated by carbon were obtained by adding enough surfactants that decomposed into carbon after the chemical synthesis and postannealing of the A1 FePt nanoparticles. ... -
Rapid thermal annealing of FePt nanoparticles
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2008-07-11)We report a systematic study on rapid thermal annealing (RTA) of FePt nanoparticles. FePt particles with an average size of 8 nm were synthesized by a chemical solution method, and then annealed using RTA and conventional ... -
Rapid thermal annealing of FePt nanoparticles
(AIP, 2008-07-01)We report a systematic study on rapid thermal annealing (RTA) of FePt nanoparticles. FePt particles with an average size of 8 nm were synthesized by a chemical solution method, and then annealed using RTA and conventional ... -
Structural phase transition and ferromagnetism in monodisperse 3 nm FePt particles
(American Institute of PhysicsDepartment of Physics, The University of Texas at Arlington, 2007-08-30)FePt nanoparticles with a size of 3 nm and thermally stable room-temperature ferromagnetism are investigated. The monodisperse nanoparticles were prepared by chemical synthesis and a salt-matrix annealing technique. ... -
Structural phase transition and ferromagnetism in monodisperse 3 nm FePt particles
(AIP, 2007)FePt nanoparticles with a size of 3 nm and thermally stable room-temperature ferromagnetism are investigated. The monodisperse nanoparticles were prepared by chemical synthesis and a salt-matrix annealing technique. ...