Magnetic Properties of MWNTs-Fe3Al Composite

2009 ◽  
Vol 79-82 ◽  
pp. 1351-1354 ◽  
Author(s):  
Lai Xue Pang ◽  
De Jin Xing ◽  
Ai Qin Zhang ◽  
Jing Xu ◽  
Shi Shuang Sun
Keyword(s):  
Magnetic Properties ◽  
Magnetic Property ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Soft Magnetic Property ◽  
Gradient Force ◽  
Soft Magnetic ◽  
Plasma Sintering ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Multi-walled carbon nanotubes (MWNTs)-Fe3Al was prepared by spark plasma sintering. Microstructural investigations show that MWNT remains in the composites. The magnetic properties were investigated with alternating gradient force magnetometer, which shows that the composites still display good soft magnetic property. The MWNTs-Fe3Al composites have a similar magnetic hysteresis loops to that of Fe3Al, indicating the good soft magnetic properties of the composite. Excellent magnetic property implies that MWNT-Fe3Al composites may also have significant potential for applications in electronic-magnetic nanodevice fields.

Surfactant-Templated Synthesis and Magnetic Properties of Ordered Nanostructured Fe3O4

2012 ◽  
Vol 427 ◽  
pp. 169-172
Author(s):  
Xiu Jie Ji ◽  
Bin Wang ◽  
Chao Liu ◽  
Bo Wen Cheng ◽  
Jun Song ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Property ◽  
Saturation Magnetization ◽  
Phase Structure ◽  
Sodium Dodecyl ◽  
Soft Magnetic Property ◽  
Soft Magnetic ◽  
Two Phase ◽  
Templated Synthesis ◽  
Water Media

Surfactant-templated synthesis of ordered nanostructured materials attracts more and more attention. In this paper, ordered nanostructured Fe3O4powder was synthesized via a facile reflux method in ethanol-water media using sodium dodecyl sulphonate (SDS, C12H25SO3Na) as template. XRD and VSM were used to characterize the ordered nanostructure, inorganic phase and magnetic properties. Results show that Fe3O4powder is of an ordered nanostructure of 7.6 nm which was detected by SAXRD and the inorganic phase is composed of cubic Fe3O4nanocrystals. VSM analysis shows that the ordered nanostructured Fe3O4exhibits a two-phase structure and a soft magnetic property with a saturation magnetization of 40emu/g.

THE GIANT MAGNETOSTRICTION AND MAGNETIC PROPERTIES OF THE AMORPHOUS ALTERNANT [Tb/Fe/Dy]n AND [Fe/Tb/Fe/Dy]m NANO-MULTILAYER FILMS

2008 ◽  
Vol 15 (05) ◽  
pp. 619-623
Author(s):  
X. D. LI ◽  
L. K. PAN ◽  
Z. J. ZHAO ◽  
S. M. HUANG ◽  
Y. W. CHEN ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Domain Wall Motion ◽  
Magnetic Behavior ◽  
Multilayer Films ◽  
Film Plane ◽  
Soft Magnetic ◽  
Low Field ◽  
Giant Magnetostriction

The magnetic properties and giant magnetostriction effect (GMS) of the amorphous alternant [ Tb / Fe / Dy ]n (named S1) and [ Fe / Tb / Fe / Dy ]m (named S2) nano-multilayer films have been studied. The magnetic hysteresis loops show that easy magnetic direction changes from perpendicular to the film plane (S1) to parallel to the film plane (S2). S2 has better soft magnetic properties and low-field giant magnetostriction effect than that of S1, due to the exchanging interaction between the hard GMS layer and the soft layer Fe . The different magnetic behavior is explained by considering the nature of the magnetization process, i.e. domain-wall motion and spin rotation.

scholarly journals Enhancement of Electrical Conductivity of Aluminum-Based Nanocomposite Produced by Spark Plasma Sintering

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1150
Author(s):  
Nicolás A. Ulloa-Castillo ◽  
Roberto Hernández-Maya ◽  
Jorge Islas-Urbano ◽  
Oscar Martínez-Romero ◽  
Emmanuel Segura-Cárdenas ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electrical Conductivity ◽  
Spark Plasma Sintering ◽  
Experimental Tests ◽  
Powder Morphology ◽  
Plasma Sintering ◽  
Multi Walled Carbon Nanotubes ◽  
Spark Plasma ◽  
Ball Milling Technique ◽  
Walled Carbon Nanotubes

This article focuses on exploring how the electrical conductivity and densification properties of metallic samples made from aluminum (Al) powders reinforced with 0.5 wt % concentration of multi-walled carbon nanotubes (MWCNTs) and consolidated through spark plasma sintering (SPS) process are affected by the carbon nanotubes dispersion and the Al particles morphology. Experimental characterization tests performed by scanning electron microscopy (SEM) and by energy dispersive spectroscopy (EDS) show that the MWCNTs were uniformly ball-milled and dispersed in the Al surface particles, and undesirable phases were not observed in X-ray diffraction measurements. Furthermore, high densification parts and an improvement of about 40% in the electrical conductivity values were confirmed via experimental tests performed on the produced sintered samples. These results elucidate that modifying the powder morphology using the ball-milling technique to bond carbon nanotubes into the Al surface particles aids the ability to obtain highly dense parts with increasing electrical conductivity properties.

Fabrication of large-size Fe-based glassy cores with good soft magnetic properties by spark plasma sintering

2003 ◽  
Vol 18 (9) ◽  
pp. 2115-2121 ◽  
Author(s):  
Baolong Shen ◽  
Akihisa Inoue
Keyword(s):  
Magnetic Properties ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region ◽  
Soft Magnetic Properties ◽  
Soft Magnetic ◽  
Large Size ◽  
High Relative Density ◽  
Plasma Sintering ◽  
Spark Plasma

Glassy Fe65Co10Ga5P12C4B4 alloy powders with a large supercooled liquid region of 50 K before crystallization were synthesized in the particle size range below 125 μm by Ar gas atomization. With the aim of developing a large-size Fe-based glassy core with good soft magnetic properties, the consolidation method of spark plasma sintering was applied to the Fe65Co10Ga5P12C4B4 glassy powders. The existence of the supercooled liquid region enabled us to form a large-size glassy alloy disc 20 mm in diameter and 5 mm in thickness with a high relative density of 99.7% at the glass-transition temperature of 723 K and under the external applied pressure of 300 MPa. The resulting glassy core of 18 mm in outer diameter, 10 mm in inner diameter, and 4 mm in thickness exhibits good soft magnetic properties: 1.20 T for saturation magnetization, 6 A/m for coercive force, and 8900 for maximum permeability. The good soft magnetic properties of the Fe-based bulk glassy core are attributed to the combination of the high relative density and the maintenance of the single glassy structure.

scholarly journals Optimization of Magnetic Properties of Magnetic Microwires by Post-Processing

Processes ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 1006
Author(s):  
Valentina Zhukova ◽  
Paula Corte-Leon ◽  
Lorena González-Legarreta ◽  
Ahmed Talaat ◽  
Juan Maria Blanco ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Chemical Composition ◽  
Hysteresis Loops ◽  
Structural Features ◽  
Post Processing ◽  
Soft Magnetic ◽  
Magnetic Microwires ◽  
Prepared State ◽  
Induced Magnetic Anisotropy ◽  
Selection Of

The influence of post-processing conditions on the magnetic properties of amorphous and nanocrystalline microwires has been thoroughly analyzed, paying attention to the influence of magnetoelastic, induced and magnetocrystalline anisotropies on the hysteresis loops of Fe-, Ni-, and Co-rich microwires. We showed that magnetic properties of glass-coated microwires can be tuned by the selection of appropriate chemical composition and geometry in as-prepared state or further considerably modified by appropriate post-processing, which consists of either annealing or glass-coated removal. Furthermore, stress-annealing or Joule heating can further effectively modify the magnetic properties of amorphous magnetic microwires owing to induced magnetic anisotropy. Devitrification of microwires can be useful for either magnetic softening or magnetic hardening of the microwires. Depending on the chemical composition of the metallic nucleus and on structural features (grain size, precipitating phases), nanocrystalline microwires can exhibit either soft magnetic properties or semi-hard magnetic properties. We demonstrated that the microwires with coercivities from 1 A/m to 40 kA/m can be prepared.

scholarly journals Developing a reference material set for the magnetic properties of NdFeB alloy-based hard magnetic materials

2019 ◽  
Vol 15 (1) ◽  
pp. 21-27
Author(s):  
E. A. Volegova ◽  
T. I. Maslova ◽  
V. O. Vas’kovskiy ◽  
A. S. Volegov
Keyword(s):  
Magnetic Properties ◽  
Magnetic Materials ◽  
Permanent Magnets ◽  
Magnetic Loss ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Magnetic Hysteresis Loop ◽  
Magnetic Characteristics ◽  
Hard Magnetic Materials ◽  
Certified Values

Introduction The introduction indicates the need for the use of permanent magnets in various technology fields. The necessity of measuring the limit magnetic hysteresis loop for the correct calculation of magnetic system parameters is considered. The main sources of error when measuring boundary hysteresis loops are given. The practical impossibility of verifying blocks of magnetic measuring systems element-by-element is noted. This paper is devoted to the development of reference materials (RMs) for the magnetic properties of hard magnetic materials based on Nd2Fe14B, a highly anisotropic intermetallic compound.Materials and measuring methods Nd-Fe-B permanent magnets were selected as the material for developing the RMs. RM certified values were established using a CYCLE‑3 apparatus included in the GET 198‑2017 State Primary Measurement Standard for units of magnetic loss power, magnetic induction of constant magnetic field in a range from 0.1 to 2.5 T and magnetic flux in a range from 1·10–5 to 3·10–2 Wb.Results and its discussion Based on the experimentally obtained boundary hysteresis loops, the magnetic characteristics were evaluated, the interval of permitted certified values was set, the measurement result uncertainty of certified values was estimated, the RM validity period was established and the first RM batch was released.Conclusion On the basis of conducted studies, the RM type for magnetic properties of NdFeB alloy-based hard magnetic materials was approved (MS NdFeB set). The developed RM set was registered under the numbers GSO 11059–2018 / GSO 11062–2018 in the State RM Register of the Russian Federation.

Structure, phase composition and mechanical properties of composites based on ZrO2 and multi-walled carbon nanotubes

2020 ◽  
Vol 10 ◽  
pp. 56-68
Author(s):  
A. A. Leonov ◽  
◽  
E. V. Abdulmenova ◽  
M. P. Kalashnikov ◽  
◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Phase Composition ◽  
Zirconium Carbide ◽  
Cubic Phase ◽  
Plasma Sintering ◽  
Multi Walled Carbon Nanotubes ◽  
Spark Plasma ◽  
Walled Carbon Nanotubes ◽  
Tetragonal Phase Transition ◽  
Properties Of Composites

In this work, composites based on yttria-stabilized zirconia (3Y-TZP), with additives of 1, 5 and 10 wt. % multi-walled carbon nanotubes (MWCNTs) were investigated. Samples were obtained by spark plasma sintering at a temperature of 1500 °C. It was found that MWCNTs retain their structure after high-temperature sintering, they are located along the grain boundaries of ZrO2, forming a network structure. Found that the addition of 1 wt. % MWCNTs increase the relative density of the composite from 98.3 % to 99.0 %. It is noted that nanotubes can significantly affect the phase composition of composites. Additive 5 wt. % MWCNT partially limits the monoclinic-tetragonal phase transition of ZrO2, and the addition of 10 wt. % MWCNTs leads to the formation of a cubic phase of zirconium carbide. It was found that the fracture toughness of the composite with 10 wt. % MWCNTs increases from 4.0 to 5.7 MPa·m1/2.

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