Investigation of the Property Change in FINEMET Alloy After Conventional, Pulse and Mechanical Stress Annealing

AbstractIn the present work the comparison of the effect of traditional, pulse and stress annealing is made by monitoring the important mechanical and magnetic properties of FINEMET type amorphous precursor alloy. The magnetic properties were determined from the shape of magnetization curve (coercive force, anisotropy) during various heat treatments and the mechanical properties were measured using brittleness test. The traditional heat treatments were performed in resistance furnace and the magnetic measurements were performed in astatic magnetometer. The pulse and stress annealing (as well as their combinations) were carried out inside in the magnetometer. The temperature of pulse heat treatments is regulated with the length of current pulse flowing through the sample. After each pulses the magnetization curves were measured in-situ, in the magnetometer.

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Temperature dependence of the magnetic properties of reservoir rocks and minerals and implications for in situ borehole predictions of petrophysical parameters

Geophysics ◽

10.1190/geo2011-0282.1 ◽

2012 ◽

Vol 77 (3) ◽

pp. WA211-WA221 ◽

Cited By ~ 2

Author(s):

Arfan Ali ◽

David K. Potter

Keyword(s):

Magnetic Properties ◽

Magnetic Susceptibility ◽

Temperature Dependence ◽

High Field ◽

Magnetic Measurements ◽

Clay Content ◽

Petrophysical Parameters ◽

Reservoir Rocks ◽

Fluid Permeability

Recent work has shown strong correlations between magnetic susceptibility and key petrophysical parameters such as clay content and fluid permeability. The magnetic measurements in previous work were mainly undertaken at ambient (room temperature) conditions on core samples. The present study involved theoretical modeling and experimentation on the temperature dependence of the magnetic properties (mass magnetization and magnetic susceptibility) of reservoir rocks and minerals over a range of low and high applied fields. It paves the way for correctly interpreting borehole magnetic susceptibility measurements, and accurately predicting petrophysical properties in situ, from a potentially new suite of low and high field borehole magnetic tools. The temperature dependent magnetic susceptibility measurements provide an improved means of quantifying the diamagnetic versus paramagnetic mineral content in reservoir rocks compared to a single ambient measurement. Paramagnetic clays, such as illite, are important in controlling the fluid permeability in many of these samples, and we again saw correlations between the magnetic measurements, paramagnetic clay content, and permeability. We also show how to derive ferrimagnetic mineral hysteresis curves by subtracting the high field magnetic data from the total signal. The resulting magnetic hysteresis curves give important information concerning the content (often only a few ppm, which X-ray diffraction cannot detect), mineralogy, and domain state of the ferrimagnetic particles.

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Photoluminescence and Magnetic Properties of Undoped and (Mn, Co) co-doped ZnO Nanoparticles

Current Nanoscience ◽

10.2174/1573413715666191010162626 ◽

2020 ◽

Vol 16 (4) ◽

pp. 655-666

Author(s):

Mona Rekaby

Keyword(s):

Magnetic Properties ◽

Zno Nanoparticles ◽

Room Temperature ◽

Magnetic Measurements ◽

Structural Defects ◽

Ferromagnetic Behavior ◽

Secondary Phases ◽

Antiferromagnetic Ordering ◽

Doped Zno ◽

Co Doped

Objective: The influence of Manganese (Mn2+) and Cobalt (Co2+) ions doping on the optical and magnetic properties of ZnO nanoparticles was studied. Methods: Nanoparticle samples of type ZnO, Zn0.97Mn0.03O, Zn0.96Mn0.03Co0.01O, Zn0.95Mn0.03 Co0.02O, Zn0.93Mn0.03Co0.04O, and Zn0.91Mn0.03Co0.06O were synthesized using the wet chemical coprecipitation method. Results: X-ray powder diffraction (XRD) patterns revealed that the prepared samples exhibited a single phase of hexagonal wurtzite structure without any existence of secondary phases. Transmission electron microscope (TEM) images clarified that Co doping at high concentrations has the ability to alter the morphologies of the samples from spherical shaped nanoparticles (NPS) to nanorods (NRs) shaped particles. The different vibrational modes of the prepared samples were analyzed through Fourier transform infrared (FTIR) measurements. The optical characteristics and structural defects of the samples were studied through Photoluminescence (PL) spectroscopy. PL results clarified that Mn2+ and Co2+ doping quenched the recombination of electron-hole pairs and enhanced the number of point defects relative to the undoped ZnO sample. Magnetic measurements were carried out at room temperature using a vibrating sample magnetometer (VSM). (Mn, Co) co-doped ZnO samples exhibited a ferromagnetic behavior coupled with paramagnetic and weak diamagnetic contributions. Conclusion: Mn2+ and Co2+ doping enhanced the room temperature Ferromagnetic (RTFM) behavior of ZnO. In addition, the signature for antiferromagnetic ordering between the Co ions was revealed. Moreover, a strong correlation between the magnetic and optical behavior of the (Mn, Co) co-doped ZnO was analyzed.

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A mixed-valence CuII/CuI coordination polymer based on bridged thiocyanate and in situ formed di(N-heterocyclic) sulfide: Synthesis, structure, and magnetic properties

Journal of Molecular Structure ◽

10.1016/j.molstruc.2021.130623 ◽

2021 ◽

pp. 130623

Author(s):

Yanfeng Cui ◽

Yuhan Ding ◽

Steven Eduardo Vilcacundo Molina ◽

Yahong Li

Keyword(s):

Magnetic Properties ◽

Coordination Polymer ◽

Mixed Valence

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A Dy(III) Fluorescent Single-Molecule Magnet Based on a Rhodamine 6G Ligand

Inorganics ◽

10.3390/inorganics9070051 ◽

2021 ◽

Vol 9 (7) ◽

pp. 51

Author(s):

Lin Miao ◽

Mei-Jiao Liu ◽

Man-Man Ding ◽

Yi-Quan Zhang ◽

Hui-Zhong Kou

Keyword(s):

Magnetic Properties ◽

Single Molecule ◽

Magnetic Relaxation ◽

Rhodamine 6G ◽

Bond Angle ◽

Magnetic Measurements ◽

Single Molecule Magnet ◽

Lanthanide Metals ◽

Process Studies ◽

Dual Functions

The complexes of lanthanide metals, especially dysprosium, can generally exhibit excellent magnetic properties. By means of modifying ligands, dual functions or even multi-functions can be achieved. Here, we synthesized an eight-coordinate Dy(III) complex 1, [Dy(HL-o)2(MeOH)2](ClO4)3·4.5MeOH, which is single-molecule magnet (SMM), and the introduction of the rhodamine 6G chromophore in the ring-opened ligand HL-o realizes ligand-centered fluorescence in addition to SMM. Magnetic measurements and ab initio calculations indicate that the magnetic relaxation for complex 1 should be due to the Raman relaxation process. Studies on magneto-structural correlationship of the rhodamine salicylaldehyde hydrazone Dy(III) complexes show that the calculated energy of the first Kramers Doublet (EKD1) is basically related to the Ophenoxy-Dy-Ophenoxy bond angle, i.e., the larger Ophenoxy-Dy-Ophenoxy bond angle corresponds to a larger EKD1.

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In situ synthesis of iron-filled nitrogen-doped carbon nanotubes and their magnetic properties

Carbon ◽

10.1016/j.carbon.2013.05.043 ◽

2013 ◽

Vol 61 ◽

pp. 647-649 ◽

Cited By ~ 8

Author(s):

Qingze Jiao ◽

Liang Hao ◽

Qingyan Shao ◽

Yun Zhao

Keyword(s):

Carbon Nanotubes ◽

Magnetic Properties ◽

In Situ Synthesis ◽

Nitrogen Doped ◽

Nitrogen Doped Carbon

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Thin film bi-epitaxy and transition characteristics of TiO2/TiN buffered VO2 on Si(100) substrates

MRS Advances ◽

10.1557/adv.2016.544 ◽

2016 ◽

Vol 1 (37) ◽

pp. 2635-2640 ◽

Cited By ~ 5

Author(s):

Adele Moatti ◽

Reza Bayati ◽

Srinivasa Rao Singamaneni ◽

Jagdish Narayan

Keyword(s):

Thin Film ◽

Thin Films ◽

Magnetic Properties ◽

Frequency Factor ◽

Misfit Strain ◽

Buffer Layers ◽

Intrinsic Defects ◽

Domain Matching Epitaxy ◽

Out Of Plane

ABSTRACTBi-epitaxial VO2 thin films with [011] out-of-plane orientation were integrated with Si(100) substrates through TiO2/TiN buffer layers. At the first step, TiN is grown epitaxially on Si(100), where a cube-on-cube epitaxy is achieved. Then, TiN was oxidized in-situ ending up having epitaxial r-TiO2. Finally, VO2 was deposited on top of TiO2. The alignment across the interfaces was stablished as VO2(011)║TiO2(110)║TiN(100)║Si(100) and VO2(110) /VO2(010)║TiO2(011)║TiN(112)║Si(112). The inter-planar spacing of VO2(010) and TiO2(011) equal to 2.26 and 2.50 Å, respectively. This results in a 9.78% tensile misfit strain in VO2(010) lattice which relaxes through 9/10 alteration domains with a frequency factor of 0.5, according to the domain matching epitaxy paradigm. Also, the inter-planar spacing of VO2(011) and TiO2(011) equals to 3.19 and 2.50 Å, respectively. This results in a 27.6% compressive misfit strain in VO2(011) lattice which relaxes through 3/4 alteration domains with a frequency factor of 0.57. We studied semiconductor to metal transition characteristics of VO2/TiO2/TiN/Si heterostructures and established a correlation between intrinsic defects and magnetic properties.

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The Use of In Situ Characterization Techniques for the Development of Intermetallic Titanium Aluminides

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.2097 ◽

2014 ◽

Vol 783-786 ◽

pp. 2097-2102 ◽

Cited By ~ 3

Author(s):

Svea Mayer ◽

Emanuel Schwaighofer ◽

Martin Schloffer ◽

Helmut Clemens

Keyword(s):

Titanium Aluminides ◽

Turbine Blades ◽

Heat Treatments ◽

Mechanical Processing ◽

Tial Alloys ◽

Solidification Processes ◽

Consistent Picture ◽

Aero Engines ◽

Multi Phase

Urgent needs concerning energy efficiency and environmental politics require novel approaches to materials design. One recent example is thereby the implementation of light-weight intermetallic titanium aluminides as structural materials for the application in turbine blades of aero-engines as well as in turbocharger turbine wheels for the next generation of automotive engines. Each production process leads to specific microstructures which can be altered and optimized by thermo-mechanical processing and / or subsequent heat-treatments. To develop sound and sustainable processing routes, knowledge on solidification processes and phase transformation sequences in advanced TiAl alloys is fundamental. Therefore, in-situ diffraction techniques employing synchrotron radiation and neutrons were used for establishing phase fraction diagrams, investigating advanced heat-treatments as well as for optimizing thermo-mechanical processing. Summarizing all results a consistent picture regarding microstructure formation and its impact on mechanical properties in advanced multi-phase TiAl alloys can be given.

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Anisotropy Energies and Critical Behavior of Ultrathin Ni(111) Films Grown on Smooth and Rough W(110) (invited)

MRS Proceedings ◽

10.1557/proc-231-289 ◽

1991 ◽

Vol 231 ◽

Cited By ~ 3

Author(s):

Yi Li ◽

K. Baberschke

Keyword(s):

Magnetic Properties ◽

Curie Temperature ◽

Film Thickness ◽

Critical Exponent ◽

Critical Behavior ◽

Induced Anisotropy ◽

Effective Anisotropy ◽

Stress Induced Anisotropy ◽

Surface Crystal

Abstract6 to 80 Å thin Ni(111) films were prepared on smooth and rough W(110) substrates in UHV and characterized by LEED and Auger spectroscopies. The measurements of the magnetic properties were carried out in situ by ferromagnetic resonance at 9 GHz between 300 and 600 K. We found that the effective anisotropies, which consist of surface, crystal, and stress induced anisotropy, increase with decreasing film thickness and temperature. The roughness of the substrate results in the drastic decrease of the effective anisotropy. This is attributed to the change of the surface structure and the stress within the Ni films. Furthermore we found that the Curie temperature Tc and the critical exponent β of Ni films on the smooth and rough substrates show no change.

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Influence of Alloying Additions on Enhancement of Soft Magnetic Properties Effect and Crystallization in FeXSiB (X=Cu, V, Co, Zr, Nb) Amorphous Alloys

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.130.171 ◽

2007 ◽

Vol 130 ◽

pp. 171-174 ◽

Cited By ~ 3

Author(s):

Z. Stokłosa ◽

G. Badura ◽

P. Kwapuliński ◽

Józef Rasek ◽

G. Haneczok ◽

...

Keyword(s):

Magnetic Properties ◽

Amorphous Alloys ◽

Crystallization Process ◽

Annealing Temperature ◽

Magnetic Measurements ◽

X Ray Diffraction ◽

Soft Magnetic ◽

X Ray ◽

Second Stage ◽

Transmission Electron

The crystallization and optimization of magnetic properties effects in FeXSiB (X=Cu, V, Co, Zr, Nb) amorphous alloys were studied by applying X-ray diffraction methods, high resolution transmission electron microscopy (HRTEM), resistometric and magnetic measurements. The temperatures of the first and the second stage of crystallization, the 1h optimization annealing temperature and the Curie temperature were determined for different amorphous alloys. Activation energies of crystallization process were obtained by applying the Kissinger method. The influence of alloy additions on optimization effect and crystallization processes was carefully examined.

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