Structural, Thermal, Morphological and Magnetic Properties of Al3+-Doped Nanostructured Spinel Nickel Ferrites

Aluminum–nickel ferrite nanostructure with a nominal composition of NiFe2-xAlxO4 (0 < x < 0.9) was synthesized by heat treatment process by employing polyvinylpyrrolidone (PVP) as a capping operator. The effects of Al3+ substitution on structural, morphological, quantitative, qualitative and magnetic properties were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron microscopy (XPS) and vibrating-sample magnetometry (VSM). Single-phase inverse spinel structure and decrease in average crystal size as Al concentration increases was acknowledged by XRD and EDX characterization. The decrease in average crystal size as Al3+ ions content increases is associated with structural effects of overall crystal size of nanostructure. The development of a thermally stable nickel ferrite above 500 °C was detected by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. The magnetic hysteresis loop measurements at room temperature (RT) with an ultimate tested magnetic field of 1.8 T shows both saturation and remnant magnetization decreases as content of Al3+ ions substitution increases. The decrease in overall magnetization is due to spin non-collinearity, weakening of magnetocrystalline anisotropy and weak super-exchange interactions.

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Influence of Zinc-Zirconium Substitution on Magnetic Properties of Ba(ZnZr)xFe12-2xO19 Hexaferrite Prepared by the Molten Salt Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.2071 ◽

2009 ◽

Vol 79-82 ◽

pp. 2071-2074 ◽

Cited By ~ 2

Author(s):

Hai Feng Li ◽

Rong Zhou Gong ◽

Xian Wang ◽

Li Ren Fan ◽

Gang He ◽

...

Keyword(s):

Magnetic Properties ◽

Molten Salt ◽

Magnetic Hysteresis ◽

Magnetic Hysteresis Loop ◽

Chemical Compositions ◽

Molten Salt Method ◽

Vibrating Sample Magnetometer ◽

Hexagonal Ferrites ◽

X Ray Diffraction ◽

X Ray

M-type hexaferrites Ba(ZnZr)xFe12-2xO19 (x=0, 0.5, 1.0, 1.5) powders, have been synthesized by molten salt method, where x varies from 0 to 1.5 in steps of 0.5. X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer(VSM) were used to analyze the structures and magnetic properties. The results showed that, the magnetoplumbite structures for all samples calcining at 1100°C have been formed. The magnetic hysteresis loop measurements of the hexagonal ferrites powders showed that the saturation magnetization (Ms), the remanent magnetization (Mr), and the coercitivity (Hc) of ferrites depend strongly on the chemical compositions of materials. The data showed that the max Hc was obtained when substitution of x=1.0 (Hc=63.9 Oe), while the best Ms was obtained when substitution of x=0.5 (Ms=54.02 emu/g). Zn and Zr substitutions greatly modified the magnetic properties of BaM hexaferrite.

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Darstellung und magnetische Eigenschaften einiger kristalliner Nitroxidradikale/Synthesis and Magnetic Properties of Some Crystalline Nitroxide Radicals

Zeitschrift für Naturforschung B ◽

10.1515/znb-2000-0703 ◽

2000 ◽

Vol 55 (7) ◽

pp. 567-575 ◽

Cited By ~ 2

Author(s):

K. Griesar ◽

E. A. Soto-Bustamante ◽

W. Haase

Keyword(s):

Differential Scanning Calorimetry ◽

Magnetic Properties ◽

Exchange Interactions ◽

Antiferromagnetic Exchange ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Nitroxide Radicals ◽

Scanning Calorimetry ◽

Polarizing Microscopy ◽

X Ray

Abstract The syntheses of different nitroxide radicals are reported. The thermal behaviour of the ni troxide radicals was examined by polarizing microscopy, differential scanning calorimetry as well as X-ray diffraction experiments. Temperature dependent magnetic susceptibility measurements were carried out in order to determine the magnetic properties of these nitroxide radicals. The majority of the radicals presented here show weak antiferromagnetic exchange interactions.

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Enhanced remanence in nanocomposite of Y1-xSmxCo5/Co ribbons obtained by melt-spinning

MRS Proceedings ◽

10.1557/opl.2016.64 ◽

2016 ◽

Vol 1816 ◽

Author(s):

José L. Hidalgo ◽

Maria C. Grijalva ◽

José A. Matutes ◽

Carlos W. Orquiz ◽

Fernando L. De Araujo ◽

...

Keyword(s):

Magnetic Properties ◽

Melt Spinning ◽

Exchange Interactions ◽

High Coercivity ◽

Nominal Composition ◽

Ferromagnetic Behavior ◽

X Ray Diffraction ◽

Hexagonal Crystal ◽

X Ray ◽

The Earth

ABSTRACTThe synthesis of alloys with nominal composition for Y1-xSmxCo5 by means of arc furnace and melt-spinning, is of critical scientific importance due that if replaced partially or completely the Samarium by the Yttrium is possible understand what contribution the earth element rare to the exchange interactions that guide to increased remnant magnetization in a nanocomposite. The alloys of Y1-xSmxCo5/Co obtained by melt-spun were characterized by x-ray diffraction with a compact hexagonal crystal structure the CaCu5 type. The alloys for nanocomposites of Y1-xSmxCo5/Co ribbons show ferromagnetic behavior with good magnetic properties, order to demonstrate this the magnetic properties were measured using a pulsed field magnetometer applying a high magnetic field in order to obtain a saturated magnetization curve and a high coercivity of 0.69 MA/m and an enhanced remanence of σr/σsat ratio equal to 0.57 were determined.

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Influence of Annealing Temperature on the Magnetic Properties of Rapidly Quenched (Nd,Pr)2-(Fe,Co,Ga,Ti,C)14B/α-Fe Nanocomposite Ribbons

Advances in Materials Science and Engineering ◽

10.1155/2013/620761 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5

Author(s):

Rahim Sabbaghizadeh ◽

Mansor Hashim ◽

Reza Gholamipour ◽

Ghazaleh Bahmanrokh ◽

Mohd Shamsul Ezzad Shafie

Keyword(s):

Magnetic Properties ◽

Melt Spinning ◽

Annealing Temperature ◽

Practical Method ◽

Nominal Composition ◽

Metallic Materials ◽

Scanning Calorimetry ◽

X Ray ◽

Microscopy Technique ◽

Different Temperatures

The effects of different heat treatment temperatures on the structure and magnetic properties of Nd-Fe-B nanocomposite permanent magnetic alloys with nominal composition of Nd9.4Pr0.6Fe74.5Co6B6Ga0.5Ti1.5C1.5have been investigated. The most practical method to produce nanostructured metallic materials is rapid solidification. Melt spinning with constant wheel speed ofV=40 m/s was employed to produce ribbons. As-spun ribbons were examined by using differential scanning calorimetry (DSC) and X-ray diffractometer (XRD) with Cu-kαradiation. The ribbons were annealed at different temperatures in order to extract the best magnetic properties. The XRD and electron microscopy technique results confirm that grains are in the size of less than 50 nm. In addition, optimum magnetic properties were obtained at 700°C annealed temperature.

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Novel Polyimide/Copper-Nickel Ferrite Composites with Tunable Magnetic and Dielectric Properties

Polymers ◽

10.3390/polym13101646 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1646

Author(s):

Corneliu Hamciuc ◽

Mihai Asandulesa ◽

Elena Hamciuc ◽

Tiberiu Roman ◽

Marius Andrei Olariu ◽

...

Keyword(s):

Dielectric Properties ◽

Nickel Ferrite ◽

Scanning Calorimetry ◽

X Ray ◽

Broadband Dielectric Spectroscopy ◽

Copper Nickel ◽

Low Dielectric ◽

Magnetic Remanence ◽

Polyimide Matrix ◽

Ferrite Composites

Heat-resistant magnetic polymer composites were prepared by incorporating cerium-doped copper-nickel ferrite particles, having the general formula Ni1-xCuxFe1.92Ce0.08O4 (x: 0.0, 0.3, 0.6, 1.0), into a polyimide matrix. The effects of particle type and concentration on the thermal, magnetic, and electrical properties of the resulting composites were investigated. The samples were characterized by FTIR, scanning electron microscopy, X-ray diffractometry, thermogravimetric analysis, differential scanning calorimetry, vibrating sample magnetometer, and broadband dielectric spectroscopy. The composites exhibited high thermal stability, having initial decomposition temperatures between 495 and 509 °C. Saturation magnetization (Ms), magnetic remanence (Mr), and coercivity (Hc) were found in range of 2.37–10.90 emu g−1, 0.45–2.84 emu g−1, and 32–244 Oe, respectively. The study of dielectric properties revealed dielectric constant values of 3.0–4.3 and low dielectric losses of 0.016–0.197 at room temperature and a frequency of 1 Hz.

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Mn-Induced Thermal Stability of L10 Phase in Fept Magnetic Nanoscale Ribbons

Nanomaterials ◽

10.3390/nano10071278 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1278

Author(s):

Alina Daniela Crisan ◽

Aurel Leca ◽

Dan Pantelica ◽

Ioan Dan ◽

Ovidiu Crisan

Keyword(s):

Rare Earth ◽

Single Phase ◽

Permanent Magnets ◽

Magnetic Hysteresis ◽

Ternary Alloys ◽

Large Temperature ◽

Nominal Composition ◽

X Ray Diffraction ◽

X Ray ◽

Operation Conditions

Magnetic nanoscale materials exhibiting the L10 tetragonal phase such as FePt or ternary alloys derived from FePt show most promising magnetic properties as a novel class of rare earth free permanent magnets with high operating temperature. A granular alloy derived from binary FePt with low Pt content and the addition of Mn with the nominal composition Fe57Mn8Pt35 has been synthesized in the shape of melt-spun ribbons and subsequently annealed at 600 °C and 700 °C for promoting the formation of single phase, L10 tetragonal, hard magnetic phase. Proton-induced X-ray emission spectroscopy PIXE has been utilized for checking the compositional effect of Mn addition. Structural properties were analyzed using X-ray diffraction and diffractograms were analyzed using full profile Rietveld-type analysis with MAUD (Materials Analysis Using Diffraction) software. By using temperature-dependent synchrotron X-ray diffraction, the disorder–order phase transformation and the stability of the hard magnetic L10 phase were monitored over a large temperature range (50–800 °C). A large interval of structural stability of the L10 phase was observed and this stability was interpreted in terms of higher ordering of the L10 phase promoted by the Mn addition. It was moreover found that both crystal growth and unit cell expansion are inhibited, up to the highest temperature investigated (800 °C), proving thus that the Mn addition stabilizes the formed L10 structure further. Magnetic hysteresis loops confirmed structural data, revealing a strong coercive field for a sample wherein single phase, hard, magnetic tetragonal L10 exists. These findings open good perspectives for use as nanocomposite, rare earth free magnets, working in extreme operation conditions.

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

Reference materials ◽

10.20915/2077-1177-2019-15-1-21-27 ◽

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.

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Fabrication of Hexagonal Ni Micro/Nano Plates by a Facile Hydrothermal Reduction Route

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.898.173 ◽

2014 ◽

Vol 898 ◽

pp. 173-176

Author(s):

Jun Zhang ◽

Hai Rui Yao ◽

Hua Bo Li ◽

Jing Jing Li ◽

Xiao Kang Bai

Keyword(s):

Magnetic Hysteresis ◽

Magnetic Hysteresis Loop ◽

Face Centered Cubic ◽

Hydrothermal Route ◽

Nickel Metal ◽

Structure Directing Agent ◽

X Ray ◽

Facile Hydrothermal Route ◽

Face Centered ◽

Hydrothermal Reduction

Hexagonal Ni micro/nanoplates were successfully prepared via a facile hydrothermal route using the polyvinylpyrrolidone as structure-directing agent. It has been verified from x-ray powder diffraction and transmission electronic microscopy that as-prepared products with high purity and fine dispersity belong to face-centered cubic microstructure of nickel metal. The magnetic hysteresis loop of the hexagonal Ni micro/nanoplates exhibits the ferromagnetic characteristics, and its coercivity increases by 25 % in comparison with the bulk nickel materials. The possible mechanism of the formation of hexagonal micro/nanoplates was suggested.

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Influence of Gd Addition on the Structure and Capability of Ni-Mn-In Metamagnetic Shape Memory Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.950 ◽

2012 ◽

Vol 535-537 ◽

pp. 950-953

Author(s):

Li Na Bai ◽

Gui Xing Zheng ◽

Zhi Jian Duan ◽

Jian Jun Zhang

Keyword(s):

Differential Scanning Calorimetry ◽

Magnetic Properties ◽

Magnetic Property ◽

Transition Temperature ◽

Martensitic Transformation ◽

Room Temperature ◽

Vibrating Sample Magnetometry ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray

The influences of Gd concentration on martensitic transformation and magnetic properties of NiMnIn alloys were investigated by differential scanning calorimetry (DSC) , vibrating sample magnetometry (VSM), X-ray diffraction (XRD) and etc. It is Observed through the experiment: the addition of Gd enhances martensite transition temperature;X-ray diffraction analysis of experimental alloys is revealed that to the mixture is martensite and austenite at room temperature; content of Gd is not proportional to the improvement of magnetic property.

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Structural and Magnetic Properties of Nano Composite (Ni1-xSrx Fe12 O19) Prepared by Sol-gel

NeuroQuantology ◽

10.14704/nq.2021.19.10.nq21152 ◽

2021 ◽

Vol 19 (10) ◽

pp. 20-28

Author(s):

Dhifaf Hussain Hassan ◽

Sabah Jalal Fathi

Keyword(s):

Magnetic Properties ◽

Hysteresis Loop ◽

Quaternary Structure ◽

Sol Gel ◽

Magnetic Hysteresis ◽

Magnetic Hysteresis Loop ◽

Cubic Phase ◽

X Ray Diffraction ◽

Two Phases ◽

Hematite Fe2o3

The compound was prepared by sol-gel method for spontaneous combustion with certain weight ratios (x=0.0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9), the samples were calcined at a temperature (900oC) for a period of two hours(2h), then studied its structural and magnetic properties.one of the most prominent results that we obtained from the X-ray diffraction technique (XRD) is that compound has several phases. Where the sample (NiFe2O4) appeared to be polycrystalline and the dominant phase in it is the cubic phase, while the other phase is (Hematite)(Fe2O3) A crystal structure rhomboid (Rhombohedral), in addition to these two phases, the phase with the existing quaternary structure appeared (Sr2Fe2O5) its called (Orthorhombic). The results of the magnetic properties that were obtained through the (VSM) device, and one of the most important of these properties is the magnetic hysteresis loop by analyzing the magnetic hysteresis loop at (x=0.3), where the least area of the hysteresis loop or the least width of the hysteresis loop One of the most important parameters of the magnetic properties is the saturation magnetism (μS) and its value ranges from (19.76-3.86) (emu/gr), the highest value was at (X=0.3) and its value is (19.76emu/gr) and in general its value decreases with increasing concentration of strontium. The residual magnetism (Mr) ranges between (7.45-1.58) (emu/gr), where it reached its highest value at (x=0.3) and its value is (7.45emu/gr), and generally its value decreases with increasing concentration of strontium. In addition to that, there is another parameter which is coercion or Magnetic coercivity (Hc) ranges in value (1751.104-209.26) (Oe), reaching its lowest value at (x=0.3), and then increases with increasing strontium concentration until it reaches its highest value at (x=0.9), where it reached its value is (1751.104Oe). The square rate represented by the symbol (μi) has high values. This means that there is a mutual coupling between the soft and hard magnetic phases, which was the highest value at (x=0.3) and its value is (4.93).

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