CRYSTALLIZATION PROGRESS AND MAGNETIC PROPERTY OF Fe–Zr(Nb)–B AMORPHOUS-NANOCRYSTALLINE ALLOY

2012 ◽  
Vol 26 (11) ◽  
pp. 1250088 ◽  
Author(s):  
Z. HUA ◽  
Y. M. SUN ◽  
W. Q. YU ◽  
M. B. WEI
Keyword(s):  
Amorphous Alloys ◽  
Melt Spinning ◽  
Annealing Temperature ◽  
Nanocrystalline Alloy ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Annealing Stage ◽  
X Ray ◽  
Specific Saturation Magnetization ◽  
Change Trend

Fe 81 Zr 9 B 10 and Fe 81 Zr 7 Nb 2 B 10 amorphous alloys were prepared by melt-spinning. The microstructures and magnetic properties of the alloys annealed at various temperatures were investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The crystallization progresses of Fe 81 Zr 9 B 10 and Fe 81 Zr 7 Nb 2 B 10 amorphous alloys are as follows: amorphous → residual amorphous + α- Fe → α- Fe + Fe 3 Zr + ZrFe 2 and amorphous → residual amorphous + α- Fe → α- Fe + Fe 2 Zr , respectively. The grain size (D) of α- Fe in Fe 81 Zr 7 Nb 2 B 10 alloy is smaller than that in Fe 81 Zr 9 B 10 alloy at every annealing stage. The change trend of specific saturation magnetization (Ms) of Fe 81 Zr 7 Nb 2 B 10 alloy with increasing annealing temperature (Ta) is the same as that of Fe 81 Zr 9 B 10 alloy. However, the change trend of coercivity (Hc) of Fe 81 Zr 7 Nb 2 B 10 alloy with increasing annealing temperature is different from that of Fe 81 Zr 9 B 10 alloy, which abruptly deteriorates at 600°C.

Crystallization processes and magnetic properties of Fe78Co2Zr8Nb2B10-xGex (x = 0, 1, 2, 3) amorphous alloys

2014 ◽  
Vol 28 (20) ◽  
pp. 1450160
Author(s):  
Z. Hua ◽  
B. Zuo ◽  
Y. M. Sun ◽  
X. N. Wang ◽  
L. R. Dong ◽  
...  
Keyword(s):  
Magnetic Property ◽  
Amorphous Alloys ◽  
Melt Spinning ◽  
Crystallization Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Initial Stage ◽  
Different Temperatures ◽  
Change Trend

Fe 78 Co 2 Zr 8 Nb 2B10-x Ge x (x = 0, 1, 2, 3) amorphous alloys were prepared by melt-spinning and annealed at different temperatures. The microstructures and magnetic property were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM), respectively. The crystallization processes of Fe 78 Co 2 Zr 8 Nb 2 B 10 amorphous alloy at different quenching rates are similar and complex. The α- Fe ( Co ) and α- Mn type phases are observed in their initial stage of crystallization process. Hc increases with increasing annealing temperature in general. Only α- Fe ( Co ) phase is observed in the initial stage of the crystallization processes of Fe 78 Co 2 Zr 8 Nb 2 B 10-x Ge x (x = 0, 1, 2, 3) alloys. The change trend of coercivity is complex compared with Ge -free samples. The magnetic property of Fe 78 Co 2 Zr 8 Nb 2 B 7 Ge 3 is better.

Effect of heat treatment conditions on microstructure and magnetic property of Fe77Co2Zr9B10Cu2 alloy

2014 ◽  
Vol 28 (10) ◽  
pp. 1450083 ◽  
Author(s):  
W. Q. Yu ◽  
X. C. Meng ◽  
B. Zuo ◽  
Y. M. Sun ◽  
B. Li ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Magnetic Property ◽  
Melt Spinning ◽  
Annealing Temperature ◽  
Grain Structure ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Treatment Conditions ◽  
Transmission Electron

Fe 77 Co 2 Zr 9 B 10 Cu 2 alloy prepared by melt-spinning was annealed at different heat treatment conditions. The thermal property, microstructure and magnetic property of alloys were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). Fe 77 Co 2 Zr 9 B 10 Cu 2 alloy as-quenched is a mixture of α- Fe ( Co ) phase, H -phase and amorphous phase. With increasing annealing temperature, the H -phase transforms to α- Fe ( Co ) phase. Coercivity (Hc) of Fe 77 Co 2 Zr 9 B 10 Cu 2 alloy annealed at 600°C for 40 min followed by furnace cooling reaches the minimum value, which is attributed to the small and homogeneous α- Fe ( Co ) grain structure.

Crystallization process and magnetic property of Fe81Zr3Nb6B10 alloy

2015 ◽  
Vol 29 (31) ◽  
pp. 1550196 ◽  
Author(s):  
Y. M. Sun ◽  
W. Q. Yu ◽  
D. Long ◽  
Y. Zhang ◽  
Z. Hua
Keyword(s):  
Thermal Analysis ◽  
Solid Solution ◽  
Magnetic Property ◽  
Differential Thermal Analysis ◽  
Melt Spinning ◽  
Crystallization Process ◽  
Annealing Temperature ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray

[Formula: see text] amorphous alloy was prepared by melt-spinning and annealed at various temperatures. The thermal property, microstructure and magnetic property were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The crystallization process of [Formula: see text] alloy is as follow: Amorphous [Formula: see text] residual amorphous [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] solid solution. Coercivity [Formula: see text] of [Formula: see text] alloy changes complexly, which abruptly deteriorates at 843 K and then softens with increasing annealing temperature [Formula: see text].

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

2007 ◽  
Vol 130 ◽  
pp. 171-174 ◽  
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.

SIZE-INDUCED EFFECTS IN NANOSTRUCTURED NiFe2O4

2010 ◽  
Vol 24 (30) ◽  
pp. 5973-5985
Author(s):  
M. GUNES ◽  
H. GENCER ◽  
T. IZGI ◽  
V. S. KOLAT ◽  
S. ATALAY
Keyword(s):  
Electron Microscopy ◽  
Annealing Temperature ◽  
Structural Parameters ◽  
Hydrothermal Process ◽  
Lattice Parameter ◽  
Effect Of Temperature ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

NiFe 2 O 4 nanoparticles were successfully prepared by a hydrothermal process, and the effect of temperature on them was studied. The particles were annealed at various temperatures ranging from 413 to 1473 K. Studies were carried out using powder X-ray diffraction, scanning electron microscopy, infrared spectroscopy, differential thermal analysis, thermogravimetric analysis and a vibrating sample magnetometer. The annealing temperature had a significant effect on the magnetic and structural parameters, such as the crystallite size, lattice parameter, magnetization and coercivity.

Microcrystallinity in α-Si, Ge:H, F Alloys

1986 ◽  
Vol 70 ◽  
Author(s):  
D. S. Shen ◽  
J. Kolodzey ◽  
D. Slobodin ◽  
J. P. Conde ◽  
C. Lane ◽  
...  
Keyword(s):  
Grain Size ◽  
Cross Sections ◽  
Amorphous Alloys ◽  
Annealing Temperature ◽  
Substrate Surface ◽  
Columnar Structure ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Temperature Anneal

ABSTRACTMicrocrystalline inclusions in hydrogenated and fluorinated amorphous silicongermanium alloys, α-Si, Ge:H, F, were studied. Microcrystals grown during RF or DC glow discharge deposition from SiF4, GeF4 and H2 consist of either pure Si or Ge. Microcrystals produced by thermal annealing of initially amorphous alloys are either microcrystalline Ge or microcrystalline Si-Ge alloys depending on the annealing temperature. Values for the grain size were calculated from X-ray diffraction (XRD) and Raman spectra. The grain size of the “grown” microcrystal ranges from 8 to 60 nm. These grown grains exhibit preferential orientation of the (220) planes parallel to the substrate surface. Microcrystals produced by high-temperature anneal are randomly oriented. Scanning electron micrographs of as-grown samples show protruding platelets several 100 nm long and several 10 nm wide. Fractured cross sections exhibit columnar structure.

scholarly journals Preparation of γ-Fe2O3/Ni2O3/FeCl3(FeCl2) Composite Nanoparticles by Hydrothermal Process Useful for Ferrofluids

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Qingmei Zhang ◽  
Jian Li ◽  
Hua Miao ◽  
Jun Fu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hydrothermal Process ◽  
Composite Nanoparticles ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Amorphous Precursor ◽  
Outermost Layer ◽  
X Ray ◽  
Specific Saturation Magnetization ◽  
Transmission Electron

Using a hydrothermal process in FeCl2 solution, γ-Fe2O3/Ni2O3/FeCl3(FeCl2) composite nanoparticles were obtained from the FeOOH/Ni(OH)2 precursor prepared by coprecipitation. The precursor and the as-prepared nanoparticles were investigated by vibrating sample magnetometer (VSM), X-ray diffraction (XRD), energy disperse X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The experimental results showed that the paramagnetic amorphous precursor, in which Ni(OH)2 is formed outside FeOOH, is transformed to ferrimagnetic γ-Fe2O3/Ni2O3 composite when it is processed in FeCl2 solution (0.25, 0.50, 1.00 M) in an autoclave at 100°C for 1 hr. In addition, the dismutation reaction of FeCl2 produces FeCl3 and Fe. Some FeCl3 and little FeCl2 can be absorbed to form γ-Fe2O3/Ni2O3/FeCl3(FeCl2) composite nanoparticles in which Ni2O3 forms outside the γ-Fe2O3 core and the outermost layer is FeCl3 (FeCl2). The content of FeCl3 (FeCl2) in the particles increased, and the magnetization of the particles decreased with the concentration of FeCl2 solution increasing in the hydrothermal process. The FeCl3 (FeCl2) surface is chemically passive and nonmagnetic (paramagnetic). Accordingly, the composite nanoparticles are chemically stable, and their aggregation is prevented. The specific saturation magnetization of such composite nanoparticles can get to 57.4–62.2 emu/g and could be very suitable for synthesizing ferrofluids.

Effect of Crystallization on the Electrical Resistance and Structure of Amorphous Fe-Co-Cr-B-Si Alloys / Wpływ Krystalizacji Na Oporność Elektryczną I Strukturę Amorficznych Stopów Fe-Co-Cr-B-Si

2012 ◽  
Vol 57 (4) ◽  
pp. 1031-1039
Author(s):  
H. Solomon ◽  
N. Solomon
Keyword(s):  
Electrical Resistivity ◽  
Electrical Properties ◽  
Amorphous Alloys ◽  
Melt Spinning ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Investigation Methods ◽  
Melt Spinning Technique

The goal of this paper is to present the influence of temperature variation and iron substitution with Co on the structure and electrical properties of amorphous Fe75-xCoxCr1B7Si17 alloys (where x=1, 4, 7, and 10 at.%), obtained by melt-spinning technique. The electrical resistivity of the samples was measured by using a usual four-probe method from -160°C to 750°C. The electrical resistivity was also measured at room temperature for the amorphous Fe75-xCoxCr1B7Si17 ribbons annealed at various temperatures for different holding time. The annealed samples were also investigated by Vickers microhardness test. The amorphous structure of tested materials was examined by X-ray diffraction (XRD), Mossbauer spectroscopy, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) methods. Experimental results confirmed the utility of applied investigation methods and the influence of the Co content and annealing process on the crystallization, structure and electrical properties of examined amorphous alloys.

Relationship of glass formation ability and eutectics in ternary Ni–Zr–B system

2004 ◽  
Vol 19 (9) ◽  
pp. 2523-2526 ◽  
Author(s):  
W.S. Sun ◽  
H.F. Zhang ◽  
B.Z. Ding ◽  
Z.Q. Hu
Keyword(s):  
Intermetallic Compounds ◽  
Glass Formation ◽  
Amorphous Alloys ◽  
Melt Spinning ◽  
Ternary Eutectic ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Glass Formation Ability ◽  
Relationship Of

Five Ni–Zr–B ternary eutectic alloys were synthesized by means of melt spinning and were found “amorphous” by standard surface x-ray diffraction. The thermal stability was determined by differential scanning calorimetry. Glass-formation ability (GFA) was characterized by reduced glass transition temperature among the five “amorphous” alloys. The existence of intermetallic compounds which are structurally complex and have bigger lattice parameters is proved to enhance the higher GFA. The effective suppression of nucleation and growth of intermetallic compounds plays a very important role for the glass formation.

Tailoring the structural and magnetic property of nanocrystalline MnxZn1-xFe2O4synthesized by citrate route method

MRS Advances ◽  
2017 ◽  
Vol 2 (49) ◽  
pp. 2763-2768
Author(s):  
D. K. Tiwari ◽  
S. E. Almanza-Morales ◽  
L. M. Morales-Villagómez ◽  
M.O. Alonso-Pérez ◽  
Prakhar Sengar ◽  
...  
Keyword(s):  
Annealing Temperature ◽  
Magnetic Measurements ◽  
Xrd Analysis ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Higher Temperature ◽  
Mn Substitution ◽  
Average Size ◽  
Synthesized Materials

ABSTRACTNanocrystalline MnxZn1-xFe2O4with the varying concentration of Mn (x= 0.25, 0.50) have been synthesized by citrate route method. The effect of annealing temperature on structural and magnetic properties of as-synthesized materials was studied. The X-ray diffraction (XRD) analysis revealed the improved crystallinity and purity of the samples at high temperature annealing. Also, the increase in the annealing temperature yielded nanocrystals with bigger crystallite size. The samples annealed at higher temperature were analyzed by TEM which showed the formation of irregular polycrystalline particles with average size in the range of 150-180 nm. The magnetic measurements were taken using vibrating sample magnetometer and displayed the superparamagnetic behavior of the prepared materials. Also, the increase in magnetization was observed with Mn substitution.

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