Phase Ferromagnetic
Mostrando 1-12 de 48 artigos, teses e dissertações.
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1. Iron oxide/titania composites for radar absorbing material (RAM) applications
Resumo Compósitos de óxido de ferro/titânia foram sintetizados pelo método de precipitação. A quantidade de óxido de ferro foi variada nos compósitos. Fase única (anatásio) foi obtida para a fração em massa de 0-20% e três fases (anatásio, magnetita e hematita) foram encontradas para as frações de 30% e 40% de óxido de ferro. O tamanho de cr
Cerâmica. Publicado em: 15/08/2019
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2. Influence of defects on the irreversible phase transition in the Fe-Pd doped with Co and Mn
ABSTRACT The appearance of BCT martensite in Fe-Pd-based ferromagnetic shape memory alloys, which develops at lower temperatures than the thermoelastic martensitic transition, deteriorates the shape memory properties. In a previous work performed in Fe70Pd30, it was shown that a reduction in defects density reduces the non thermoelastic FCT-BCT transformatio
Matéria (Rio J.). Publicado em: 19/07/2018
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3. Comportamiento magnético del acero AISI 304 en ensayos de tracción uniaxial
ABSTRACT During the magnetization process of a ferromagnetic material, the magnetic domain walls are forced to move due to the magnetic field influence. The domain walls must overcome the stress produced by the pinning sites (grain boundary, dislocations, inclusions, etc.), producing discrete jumps in the magnetization. These jumps can be detected with a sen
Matéria (Rio J.). Publicado em: 19/07/2018
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4. Use of Magnetic Barkhausen Noise (MBN) to Follow Up the Formation of Sigma Phase in Saf2205 (UNS S31803) Duplex Stainless Steel
Abstract Duplex stainless steels have a structure normally composed of austenite and ferrite in approximately equal proportions. In order to attain control of its fabrication processes and performance, it is important to understand its microstructural evolution, due to the formation of intermetallic phases such as sigma (σ) and chi (χ), which may cause a s
Mat. Res.. Publicado em: 01/08/2016
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5. Crystallization in Rapidly Quenched Fe-B-Si System with Additions of C and Cu
Glass formability and phase transformations in rapidly quenched ferromagnetic nano-structured (Fe85B15-xSix)98-yC2Cuy (where x=0; 5 and y=0; 1) systems were investigated. The consecutive crystallization stages of bcc-Fe and borides were determined by resistometry, differential scanning calorimetry and by thermogravimetry, where the values of important transf
Mat. Res.. Publicado em: 17/11/2015
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6. Synthesis and characterization of Fe3O4 nanoparticles with perspectives in biomedical applications
Nowadays the use of magnetic nanoparticles (MNP) in medical applications has exceeded expectations. In molecular imaging, MNP based on iron oxide coated with appropriated materials have several applications in vitro and in vivo studies. For applications in nanobiotechnology these MNP must present some characteristics such as size smaller than 100 nanometers,
Mat. Res.. Publicado em: 29/04/2014
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7. Giant reversible magnetocaloric effect in flower-like β-Co(OH)2 hierarchical superstructures self-assembled by nanosheets
A facile hydrothermal strategy is proposed to synthesize flower-like β-Co(OH)2 hierarchical microspherical superstructures with a diameter of 0.5-1.5 μm, which are self-assembled by β-Co(OH)2 nanosheets with the average thickness ranging between 20 and 40 nm. The magnetocaloric effect associated with magnetic phase transitions in Co(OH)2 superstructures h
Mat. Res.. Publicado em: 11/10/2013
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8. Pressure Influence on the Stability and Formation of γ - Fe4N when Transformed into Fe4O
The improved technology has allowed the study of electronic structure of solids with a complex crystalline structure and containing various atoms, different in the unit cell, and thus we can calculate the energy of formation and obtaining the bulk modulus and cohesive energy, which lets us discussing the compounds stability. The importance of this work is to
Mat. Res.. Publicado em: 23/07/2013
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9. An analysis on electric and magnetic behaviour on an induction planar actuator
The induction planar actuator, i.e. IPA, proposed in this study presents an electromagnetic structure formed by a static ferromagnetic core with an aluminium plate that corresponds to the secondary, and a mover, also called primary. The latter comprehends two three-phase windings, mounted in an armature core, which are orthogonal to each other. When they are
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-06
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10. Zeros de Fisher e aspectos críticos do modelo de Ising dipolar / Fisher\ s zeros and critical aspects of the dipolar Ising model
We study the critical behavior of the dipolar Ising model on two-dimensional regular lattices. This model presents a phenomenologically rich scenario due to the effect of frustration caused by the competition between the pure Ising interaction and the dipolar one. To study the criticality of this model we apply finite size scaling relations for the partition
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 06/06/2011
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11. Estudo de materiais magnéticos através de técnicas fototérmicas : efeito magnetocalórico e filmes finos / Study of magnetic materials using photothermal techniques : magnetocaloric effect and thin films
The magnetocaloric effect (MCE) has been widely studied because of its possible application in magnetic refrigeration. The search for suitable materials has intensified over the last decade, with a demand not only for the preparation of new materials but also for their complete characterization. The aim of this work is to apply the photothermal techniques to
Publicado em: 2010
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12. Simulações numéricas de Monte Carlo aplicadas no estudo das transições de fase do modelo de Ising dipolar bidimensional / Numerical Monte Carlo simulations applied to study of phase transitions in two-dimensional dipolar Ising model
Two-dimensional spin model with nearest-neighbor ferromagnetic interaction and long-range dipolar interactions exhibit a rich phase diagram, whose characteristics have been exploited by several studies in the recent literature. Furthermore, the possibility of explain observed phenomena in ultrathin magnetic films, which have many technological applications,
Publicado em: 2009