scholarly journals Phase Formation and Magnetic Properties of Melt Spun and Annealed Nd-Fe-B Based Alloys with Ga Additions

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 497
Author(s):  
Shchetinin ◽  
Aggrey ◽  
Bordyuzhin ◽  
Savchenko ◽  
Gorshenkov ◽  
...  
Keyword(s):  
Magnetic Property ◽  
Amorphous Phase ◽  
Melt Spinning ◽  
Fluorescence Analysis ◽  
Structural Transformations ◽  
X Ray Diffraction ◽  
Rich Phase ◽  
X Ray ◽  
Melt Spun ◽  
Property Changes

The structural transformations and magnetic property changes of the Nd16.2FebalCo9.9Ga0.5B7.5 (SG1, SG2) and Nd15.0FebalGa2.0B7.3 (SG3) nanocomposite alloys obtained by melt spinning in the as-quenched state and after annealing at a temperature range of 560–650 °C for 30 min were studied. The methods used were X-ray diffraction analysis, magnetic property measurements, TEM studies, X-ray fluorescence analysis and Mössbauer spectroscopy. Amorphous phase and crystalline phase Nd2Fe14B (P42/mnm) were observed in the alloy after melt spinning. The content of the amorphous phase ranged from 20% to 50% and depended on the cooling rate. Annealing of the alloys resulted in amorphous phase crystallization into Nd2Fe14B and led to the increased coercivity of the alloys up to 1840 kA/m (23.1 kOe) at 600 °C annealing for 30 min. The alloy with the maximum coercivity had a grain size of the Nd2Fe14B phase ≈50–70 nm with an Nd-rich phase between grains.

Recrystallization of Amorphous or Nanocrystalline NdBa2Cu3O7−x and GdBa2Cu3O7−x

1992 ◽  
Vol 275 ◽  
Author(s):  
T. J. Folkerts ◽  
S. I. Yoo ◽  
Youwen Xu ◽  
M. J. Kramer ◽  
K. W. Dennis ◽  
...  
Keyword(s):  
Melt Spinning ◽  
Amorphous Matrix ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Temperature Xrd ◽  
Melt Spun ◽  
Temperature Heat ◽  
Higher Temperature ◽  
Xrd Studies ◽  
Melt Spinning Technique

ABSTRACTUsing a novel melt-spinning technique, we have produced highly disordered NdBa2Cu3O7−x and GdBa2Cu3Oy−x materials. Samples which were melt-spun in an O2 environment consist of nanocrystals with the tetragonal REBa2Cu3O7−x structure: samples which were processed in an N2 environment consist of an amorphous matrix with small amounts of crystalline BaCu2O2, as shown by x-ray diffraction and electron microscopy. High temperature XRD studies indicate that the BaCu2O2 is eliminated during heating to 500°C in O2 and that the REBa2Cu3O7−x Phase recrystallizes directly from the amorphous matrix at temperatures below 800°C. Preliminary magnetization measurements show that higher temperature heat treatments are needed to restore superconductivity.

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.

scholarly journals Structure–Property Relationship in Melt-Spun Poly(hydroxybutyrate-co-3-hexanoate) Monofilaments

Polymers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 200
Author(s):  
Figen Selli ◽  
Rudolf Hufenus ◽  
Ali Gooneie ◽  
Umit Halis Erdoğan ◽  
Edith Perret
Keyword(s):  
Melt Spinning ◽  
Structure Property ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Scattering ◽  
Tensile Performance ◽  
Structure Property Relationship ◽  
Melt Spun ◽  
Structural Differences ◽  
Ice Water

Poly(hydroxybutyrate-co-3-hexanoate) (PHBH) is a biodegradable thermoplastic polyester with the potential to be used in textile and medical applications. We have aimed at developing an upscalable melt-spinning method to produce fine biodegradable PHBH filaments without the use of an ice water bath or offline drawing techniques. We have evaluated the effect of different polymer grades (mol% 3-hydroxy hexanoate, molecular weight etc.) and production parameters on the tensile properties of melt-spun filaments. PHBH monofilaments (diameter < 130 µm) have been successfully melt-spun and online drawn from three different polymer grades. We report thermal and rheological properties of the polymer grades as well as morphological, thermal, mechanical, and structural properties of the melt-spun filaments thereof. Tensile strengths up to 291 MPa have been achieved. Differences in tensile performance have been correlated to structural differences with wide-angle X-ray diffraction and small-angle X-ray scattering. The measurements obtained have revealed that a synergetic interaction of a highly oriented non-crystalline mesophase with highly oriented α-crystals leads to increased tensile strength. Additionally, the effect of aging on the structure and tensile performance has been investigated.

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].

Effect of Cooling Rate on the Transformation Temperatures of Ni50Ti36Hf14 Melt-Spun Ribbons

2018 ◽  
Vol 930 ◽  
pp. 345-348
Author(s):  
R.L. Soares ◽  
Walman Benicio Castro
Keyword(s):  
Differential Scanning Calorimetry ◽  
Martensitic Transformation ◽  
Cooling Rate ◽  
Melt Spinning ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Melt Spun ◽  
Melt Spun Ribbons ◽  
Memory Characteristics

Solidification structures and shape memory characteristics of Ni50Ti36Hf14(at.%) alloy ribbons prepared by melt spinning were investigated by means of differential scanning calorimetry and X-ray diffraction. In these experiments particular attention has been paid to change the velocity of cooling wheel from 20 to 40 m/s. Then the cooling rates of ribbons were controlled. The effect of this cooling rate on solidification structures and martensitic transformation behaviors is discussed. When the ribbon is produced at a wheel velocity of 40 m/s in melt spinning, the degree of supercooling becomes high because of its thinner thickness.

Metastable ordered austenite in rapidly solidified Fe-Al-C alloys

1989 ◽  
Vol 47 ◽  
pp. 516-517
Author(s):  
J. A. Sarreal
Keyword(s):  
Rapid Solidification ◽  
Melt Spinning ◽  
X Ray Diffraction ◽  
Austenitic Phase ◽  
X Ray ◽  
Transmission Electron ◽  
Melt Spun ◽  
Melt Spun Ribbons ◽  
Equilibrium Phases ◽  
Rapidly Solidified

Conventionally cast Fe-Al-C alloys are extremely brittle containing combinations of ferrite, carbide and other phases. Rapid solidification has the potential of altering the microstructure to subsequently change the resulting mechanical properties. An apparent conflict exist concerning the effect of rapid solidification on the resulting microstructure of these alloys. Inoue and co-workers, using transmission electron microscopy (TEM) and electron diffraction analyses, reported the presence of several non-equilibrium phases including austenite (fcc - γ) and ordered austenite (Ll2-γ') structures on alloys containing 1.7 to 2.1 C and 6 to 12 Al in weight % (w/o) on melt spun ribbons 30 μm in thickness. Han and Choo, using x-ray diffraction analysis on 30-48 μm thick melt spun ribbons concluded that this ordered fee phase is rather an austenitic phase in which phase decomposition accompanied by sideband phenomenon had occured.Single roller melt spinning technique was used to make ribbons 35-70 μm thick and 0.5-5 mm wide. X-ray diffration analysis showed single phase austenite for samples 2-6 w/o AI and 2 w/o C. Samples with 8-10 w/o AI and 2 w/o C also showed several superlattice lines in addition to the fundamental fcc peaks.

Microstructure Analysis of Melt Spun FeN foils with α''-Fe16N2Phase

MRS Advances ◽  
2016 ◽  
Vol 1 (34) ◽  
pp. 2373-2378 ◽  
Author(s):  
Md A Mehedi ◽  
Yanfeng Jiang ◽  
Jian-Ping Wang
Keyword(s):  
Auger Electron Spectroscopy ◽  
Electron Spectroscopy ◽  
Melt Spinning ◽  
Auger Electron ◽  
Diffraction Spectrum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Melt Spun ◽  
Spinning Process ◽  
Diffraction Peaks

ABSTRACTWe are reporting an approach to prepare bulk foils of α″-Fe16N2that can be directly obtained from a melt spinning process. The diffraction peaks from α″-Fe16N2phase were found in X-ray diffraction spectrum of the foil, for which a nitrogen composition of 8.7at% was found by Auger electron spectroscopy. The microstructure of this melt spun foil was analyzed. We found 600 nm subgrains inside 8 μm grains for this foil. The coercivity of the α″-Fe16N2foil was found as 222 Oe with a saturation magnetization of 223 emu/g. We analyzed the coercivity based on the microstructure and proposed a model to explain how to further improve it in melt spun FeN foils.

The Application of X-Ray Diffraction at Elevated Temperatures to Study the Mechanism of Formation of Sodium Tripolyphosphate

1961 ◽  
Vol 5 ◽  
pp. 276-284
Author(s):  
E. L. Moore ◽  
J. S. Metcalf
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Amorphous Phase ◽  
Elevated Temperatures ◽  
Sodium Tripolyphosphate ◽  
X Ray Diffraction ◽  
Mechanism Of Formation ◽  
X Ray ◽  
Temperature Form ◽  
High Temperature Form

AbstractHigh-temperature X-ray diffraction techniques were employed to study the condensation reactions which occur when sodium orthophosphates are heated to 380°C. Crystalline Na4P2O7 and an amorphous phase were formed first from an equimolar mixture of Na2HPO4·NaH2PO4 and Na2HPO4 at temperatures above 150°C. Further heating resulted in the formation of Na5P3O10-I (high-temperature form) at the expense of the crystalline Na4P4O7 and amorphous phase. Crystalline Na5P3O10-II (low-temperature form) appears after Na5P3O10-I.Conditions which affect the yield of crystalline Na4P2O7 and amorphous phase as intermediates and their effect on the yield of Na5P3O10 are also presented.

scholarly journals Mechanochemical Preparation of Slow Release Fertilizer Based on Glauconite–Urea Complexes

Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 507 ◽  
Author(s):  
Maxim Rudmin ◽  
Elshan Abdullayev ◽  
Alexey Ruban ◽  
Ales Buyakov ◽  
Bulat Soktoev
Keyword(s):  
Milling Time ◽  
Slow Release ◽  
Mechanochemical Activation ◽  
Structural Characteristics ◽  
Fluorescence Analysis ◽  
Planetary Mill ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Slow Release Fertilizers

We investigated the mechanochemical synthesis of complex slow release fertilizers (SRF) derived from glauconite. We studied the effectiveness of the mechanical intercalation of urea into glauconite using planetary and ring mills. The potassium-nitric complex SRFs were synthesized via a mechanochemical method mixing glauconite with urea in a 3:1 ratio. The obtained composites were analyzed using X-ray diffraction analysis, scanning electron microscopy, X-ray fluorescence analysis, and infrared spectroscopy. The results show that as duration of mechanochemical activation increases, the mineralogical, chemical, and structural characteristics of composites change. Essential modifications associated with a decrease in absorbed urea and the formation of microcrystallites were observed when the planetary milling time increased from 5 to 10 min and the ring milling from 15 to 30 min. Complete intercalation of urea into glauconite was achieved by 20 min grinding in a planetary mill or 60 min in a ring mill. Urea intercalation in glauconite occurs much faster when using a planetary mill compared to a ring mill.

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