scholarly journals Precipitation Behavior and Magnetic Properties of Cu-Fe-Co Alloys Containing Nanogranular Ferromagnetic-Element Particles

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
N. Wada ◽  
K. Kuwada ◽  
J. S. Kim ◽  
M. Takeguchi ◽  
M. Takeda
Keyword(s):  
Magnetic Properties ◽  
Quantum Interference ◽  
Structural Transition ◽  
Early Stage ◽  
Copper Matrix ◽  
Superconducting Quantum Interference Device ◽  
Lorentz Microscopy ◽  
The Matrix ◽  
20 Nm ◽  
Co Alloys

This work investigates the evolution of microstructures and magnetic properties during isothermal annealing of Cu-Fe-Co alloys, using electron microscopy and superconducting quantum interference device (SQUID) magnetometry. Small coherent granular precipitates composed of iron and cobalt formed in the copper matrix in the early stage of precipitation. As annealing proceeded, the precipitates lost coherency to the matrix after reaching a size of 15–20 nm and twin-like structures were consecutively introduced in the particles. The SQUID measurements revealed that the magnetic properties of the specimens correlated with the microstructural evolution. The coercive force initially increased with annealing time but decreased after reaching a peak. Lorentz Microscopy suggested that the initial large increase of magnetization was invoked by a structural transition from fcc to B2 in the precipitates.

Relationship between Microstructure and Magnetic Properties of Nano-Scale Particles Formed in Cu-Ni-(FeCo) Alloys

2018 ◽  
Vol 941 ◽  
pp. 1324-1329 ◽  
Author(s):  
Shintaro Matai ◽  
Hibiki Sakakura ◽  
Mahoto Takeda
Keyword(s):  
Magnetic Properties ◽  
Quantum Interference ◽  
Magnetic Particles ◽  
Superconducting Quantum Interference Device ◽  
Recording Technology ◽  
Treatment Conditions ◽  
Transmission Electron ◽  
Feco Alloys ◽  
The Relationship ◽  
Microstructure And Magnetic Properties

Numerous studies have been conducted to develop next-generation recording technology in spintronics. Because ultrafine magneitc particles are vital components of the technology, the interplay between the microsturcture and magnetic properties has attracted attention extensively in recent years. We focused on the relationship between the microstructure and magnetic properties of Cu-Ni-X (X=Fe, Co, FeCo) alloys comprising nanogranular magnetic particles. In this work, we prepared Cu-20 at% Ni-5 at% (FeCo), Cu-20 at% Ni-5 at% Fe, Cu-20 at% Ni-5 at% Co and examined the changes of microstructure and magnetic properties associated with heat treatments and composition. To examaine microstructural evolution of the alloy specimens, we conducted transmission electron microscope observations (TEM) with the as-quenched specimens and those aged at at 773-1073 K. We also carried out magneto-thermo gravimetry (MTG) measurements, superconducting quantum interference device (SQUID) measurements, magnetoresistance (MR) measurements and first-principles calculations based on the Koster-Korringa-Rostker (KKR) method with the Coherent Potential Approximation (CPA), to investigate the magnetic properties. The present work confirmed that the microstructure significantly changed, depending on the composition and heat treatment conditions. The present work also revealed that the magnetic properties closely correlated with the microstructure of samples.

Synthesis and Characterization of Magnetic Mesoporous Ɣ-FE2O3/SIO2

2014 ◽  
Vol 879 ◽  
pp. 128-133
Author(s):  
Nur Shuhada Shaari ◽  
Suhaina Mohd Ibrahim ◽  
Farinaa Md Jamil ◽  
Zuhana Ahmad Zubir ◽  
A.M. Abdullah ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Iron Oxide ◽  
Self Assembly ◽  
Quantum Interference ◽  
Silica Matrix ◽  
Synthesis And Characterization ◽  
Vibrating Sample Magnetometer ◽  
Superconducting Quantum Interference Device ◽  
Evaporation Induced Self Assembly

Magneticmesoporousɣ-Fe2O3/SiO2 synthesized using an evaporation-induced self-assembly (EISA) approach. The non-ionictriblock copolymer P123 was used as surfactant template with various amounts of iron oxide (1.8g-2.4g) and varied during the synthesis. Characterizations of the surface area and magnetic properties for prepared materials were done using N2-sorption analyses, and a superconducting quantum interference device interfaced with a vibrating sample magnetometer (SQUID-VSM) respectively. From this study, N2-sorption analysis indicated that most of the ɣ-Fe2O3domains of several nanometres were embedded in the silica matrix. In addition, the obtained magneticmesoporouscomposite which contains 2.3g amount ofiron oxide has revealedhigher magnetism saturation value of (4.564 emu/g) compared to other prepared samples which been evaluated by VSM analysis.

Structure and Magnetic Properties of Nanocrystalline Pd-Co and Pd-Co-Fe Layers

2007 ◽  
Vol 124-126 ◽  
pp. 907-910 ◽  
Author(s):  
András Kovács ◽  
Kazuhisa Sato ◽  
Yoshihiko Hirotsu
Keyword(s):  
Magnetic Properties ◽  
Quantum Interference ◽  
Alloy Formation ◽  
In Situ Tem ◽  
Superconducting Quantum Interference Device ◽  
Transmission Electron ◽  
Co Nanoparticles ◽  
Feco Nanoparticles ◽  
Fe Addition

The structure and magnetic properties of sequentially deposited Pd-Co and Pd-Co- Fe nanocrystals have been investigated by transmission electron microscopy (TEM) and superconducting quantum interference device magnetometer. The fcc structured PdCo alloy formation was found in binary Pd-Co nanostructured samples analysed by in situ TEM annealing. In ternary sample, the addition of Fe to Pd-Co resulted in a complex of Pd and FeCo nanoparticles. In situ TEM annealing of the ternary sample lead to the formation of L10 ordered phase. It was found that the magnetic properties of the nanoparticles were improved by Fe addition to the Pd-Co nanoparticles.

Effect of Sputtering Input Power of Co on Structure and Magnetic Properties of Fe-Co-N Thin Films

2009 ◽  
Vol 79-82 ◽  
pp. 635-638 ◽  
Author(s):  
Xin Wang ◽  
Hui Jia ◽  
Wei Tao Zheng ◽  
Wei Xu ◽  
Bei Hong Long
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Photoelectron Spectroscopy ◽  
Quantum Interference ◽  
Input Power ◽  
Superconducting Quantum Interference Device ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Composition Structure

Fe-Co-N thin films with various Co content were synthesized on Si (111) substrate using facing-target magnetron sputtering by changing sputtering input power on Co target. During deposition, the input power on Fe target was kept at 160 W. The composition, structure, and magnetic properties were examined by X-ray photoelectron spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and superconducting quantum interference device. XRD and TEM investigations showed that at lower input power of 11.2 W on Co target, the phases in the film were -(Fe,Co)4N and Co3N. Increasing sputtering input power, the content of Co in the film increased. At input power of 14 W, film contained -(Fe,Co)8N phase was produced which exhibited higher saturation magnetization (252.85 Am2/kg) and lower value of coercivity (3.66 kAm-1), corresponded to the 12% content of Co in the film.

Local Magnetic Properties of Underdoped La2-xSrxCuO4 Single Crystal Probed by Scanning Superconducting Quantum Interference Device Microscopy

2001 ◽  
Vol 40 (Part 2, No. 12B) ◽  
pp. L1359-L1361 ◽  
Author(s):  
Junpei Kasai ◽  
Yoshihiko Togawa ◽  
Takao Sasagawa ◽  
Jun-ichi Shimoyama ◽  
Kohji Kishio ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Single Crystal ◽  
Quantum Interference ◽  
Superconducting Quantum Interference Device ◽  
Superconducting Quantum Interference

scholarly journals Evaluation of the Magnetic Properties of Cosmetic Contact Lenses with a Superconducting Quantum Interference Device

2014 ◽  
Vol 13 (3) ◽  
pp. 207-214 ◽  
Author(s):  
Kagayaki KURODA ◽  
Naoki SHIRAKAWA ◽  
Yoshiyuki YOSHIDA ◽  
Kazuya TAWARA ◽  
Akihiro KOBAYASHI ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Quantum Interference ◽  
Contact Lenses ◽  
Superconducting Quantum Interference Device ◽  
Superconducting Quantum Interference

Anisotropy in FeCo Nanoparticles, a First Step

2015 ◽  
Vol 233-234 ◽  
pp. 550-553 ◽  
Author(s):  
Ghassan Khadra ◽  
Alexandre Tamion ◽  
Florent Tornus ◽  
Bruno Canut ◽  
Veronique Dupuis
Keyword(s):  
Magnetic Properties ◽  
Magnetic Anisotropy ◽  
Amorphous Carbon ◽  
Quantum Interference ◽  
Rutherford Backscattering Spectrometry ◽  
Carbon Matrix ◽  
Rutherford Backscattering ◽  
Superconducting Quantum Interference Device ◽  
Magnetic Anisotropy Energy ◽  
Feco Nanoparticles

In this article, we study the intrinsic magnetic properties of diluted FeCo clusters nanoparticles embedded in an inert amorphous carbon matrix. We report an enhancement of the magnetic anisotropy energy (MAE) after annealing demonstrated by superconducting quantum interference device (SQUID) measurements and adjustments. Rutherford backscattering spectrometry (RBS) was used to quantify the sample stoichiometry and concentration.

Synthesis, structure, and magnetic properties of iron-oxide nanowires

2006 ◽  
Vol 21 (11) ◽  
pp. 2955-2962 ◽  
Author(s):  
Matej Pregelj ◽  
Polona Umek ◽  
Boštjan Drolc ◽  
Boštjan Jančar ◽  
Zvonko Jagličič ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Magnetic Properties ◽  
Iron Oxide ◽  
Quantum Interference ◽  
Superconducting Quantum Interference Device ◽  
X Ray Diffraction ◽  
Paramagnetic Resonance ◽  
Oxide Nanowires ◽  
Transmission Electron ◽  
Electron Paramagnetic

Iron-oxide nanowires were synthesized by a hydrothermal treatment of Fe(OH)3 dispersion in NaOH. The obtained materials were first structurally investigated by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, and thermogravimetric analysis techniques. Their magnetic properties were then examined by superconducting quantum interference device and electron paramagnetic resonance methods. A typical nanowire measured 10–15 nm in diameter and 600 nm in length. All the structural and magnetic investigations were consistent with the nanowire goethite structure. The nanowire Neél transition temperature occurred at 375 K; i.e., it was lowered by 25 K with respect to the corresponding goethite bulk value. The shift in the ordering temperature was suggested to be a consequence of a growing importance of strains and surface effects at the nanoscale. We were also able to irreversibly convert goethite nanowires into hematite, by warming the sample to temperatures exceeding 530 K.

Structure, Chemical Stability and Magnetic Properties of Lanthanum Silicate Oxide Apatite Synthesized by Hydrothermal Method

2019 ◽  
Vol 966 ◽  
pp. 415-421 ◽  
Author(s):  
Yoga Trianzar Malik ◽  
Atiek Rostika Noviyanti ◽  
Nur Akbar ◽  
Iwan Hastiawan ◽  
Togar Saragi ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Hydrothermal Method ◽  
Chemical Stability ◽  
Quantum Interference ◽  
Superconducting Quantum Interference Device ◽  
X Ray Diffraction ◽  
X Ray ◽  
Low Mass ◽  
Xrd Patterns ◽  
Lanthanum Silicate

Lanthanum silicate oxides (LSOs) with modified mass target varied from 1 to 10 g were successfully synthesized using the hydrothermal method in a 100 mL autoclave. This research is aimed to study the structure, chemical stability, and magnetic properties of the LSO. From x-ray diffraction (XRD) patterns, the main peaks of LSO were observed in the sample with 1, 3, 5, and 7 g mass target while the LSO pattern did not match in the sample with 10 g mass target. The samples with low mass target resulted in better crystallinity. The chemical stabilities of the sample were then tested on LSCF perovskite cathode and showed good chemical stability with no reactivity on the cathode. The magnetic properties of the sample with 5 g mass target was measured at 100 to 300 K using a superconducting quantum interference device (SQUID). The trace of Neel temperature, TN, in LSO was not signified at this range of temperature in which referring a difference of LSO magnetic properties to the SOFC perovskite cathode. The TN of LSO was predicted below 100 K. This behavior suggested that LSO has good magnetic compatibility with the perovskite cathode.

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