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.

New, Experimental Powder Diffraction Data for Metastable Fe3B Phase Prepared According to ICDD Standards

2010 ◽  
Vol 163 ◽  
pp. 173-176
Author(s):  
Lucjan Pająk ◽  
E. Olszewska ◽  
Stanislaw Pikus ◽  
Grzegorz Dercz ◽  
Józef Rasek
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Melt Spinning ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lattice Constants ◽  
Graphite Monochromator ◽  
Best Fitting ◽  
Melt Spinning Technique

In the present work X-ray studies were performed on annealed Fe78Nb2B20 amorphous alloy prepared by melt-spinning technique. All the samples were annealed in vacuum for 1 hour at temperatures up to 800°C. For the studied alloy -Fe and Fe2B are the stable, crystalline phases. The -Fe crystallized as the first crystalline phase in the sample annealed at 350°C. On the other hand, metastable Fe3B phase appeared to be stable during annealing in 425-800°C temperature range. The best fitting of the experimental X-ray data to as jet available ICDD files was obtained for Ni3P type structure (39-1315 – S.G.: I (82)). New, experimental powder diffraction data for metastable Fe3B phase prepared according to ICDD standards were elaborated for the sample annealed at 600°C. For this sample the best agreement between the calculated values of lattice constants and positions of experimental diffraction lines was obtained. The X-ray data were collected using X-Pert Philips diffractometer equipped with curved graphite monochromator on diffracted beam. The Treor program was applied for the analysis of X-ray diffraction data.

scholarly journals Investigation of Crystalline and Tensile Properties of Carbon Nanotube-Filled Polyamide-12 Fibers Melt-Spun by Industry-Related Processes

2012 ◽  
Vol 7 (3) ◽  
pp. 155892501200700 ◽  
Author(s):  
Sanjukta Chatterjee ◽  
Felix A. Reifler ◽  
Bryan T. Chu ◽  
Rudolf Hufenus
Keyword(s):  
Mechanical Properties ◽  
Melt Spinning ◽  
Polymer Fibers ◽  
High Tensile Strength ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Polyamide 12 ◽  
Industrial Standards ◽  
Crystalline Domains

This paper addresses the influence of carbon nanotubes (CNT) on the structure and mechanical properties of high tensile strength thermoplastic polymer fibers. Polyamide (PA) fibers with different draw ratios, with and without CNTs as fillers, and having mechanical properties close to industrial standards were spun in a pilot melt spinning plant. The morphology of the fibers was investigated using optical microscopy, nuclear magnetic resonance (NMR) and 2-D wide angle x-ray diffraction (WAXD). Differential scanning calorimetry (DSC) was carried out to get an estimate of the crystallinity. For a concise interpretation of the results of the tensile measurements performed on the fibers, a parameter was developed to account for the detrimental influence of polymer extrusion on their mechanical properties. The CNTs seemed to act as sites for the growth of un-oriented crystalline domains converted from oriented regions, without yielding a mechanical reinforcing effect.

The Composition Effect on the Nanocrystallization of Finemet Amorphous Alloys

1996 ◽  
Vol 457 ◽  
Author(s):  
J. Zhu ◽  
T. Pradell ◽  
N. Clavaguera ◽  
M. T. Clavaguera-Mora
Keyword(s):  
Amorphous Alloys ◽  
Nucleation And Growth ◽  
Secondary Crystallization ◽  
Composition Effect ◽  
Phase Precipitation ◽  
X Ray Diffraction ◽  
Initial Composition ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Diffusion Controlled

ABSTRACTDifferential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Neutron Diffraction (ND) and Mössbauer Spectroscopy (MS) were used to study the nanocrystallization process of Fe73.5Cu1Nb3Si22.5–xBx (x=5, 7, 8, 9 and 12) amorphous alloys. Both the temperature range and the activation energy of Fe(Si) phase precipitation from the amorphous martrix increase with the initial B composition. The initial Si composition influences the mechanism of the nanocrystallization: for the Si rich samples, the beginning of nucleation and growth processes is interface controlled, for the B rich samples it is diffusion controlled. Secondary crystallization from the remaining amorphous is mainly Fe3B and Fe2B, the ratio of Fe3B/Fe2B being dependent on the initial composition too.

Characterizing high-pressure compressed C60 whiskers and C60 powder

2003 ◽  
Vol 18 (1) ◽  
pp. 166-172 ◽  
Author(s):  
Kun'ichi Miyazawa ◽  
Minoru Akaishi ◽  
Yusuke Kuwasaki ◽  
Tadatomo Suga
Keyword(s):  
High Pressure ◽  
Electrical Resistivity ◽  
Electrical Properties ◽  
Vickers Hardness ◽  
High Density ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Of Dislocations ◽  
Mechanical And Electrical Properties

Structural, mechanical, and electrical properties were examined for C60 whiskers, high-pressure sintered C60 whiskers, and C60 powder. A high density of dislocations was observed in the C60 whiskers, and the C60 whiskers with diameters of a few hundred nanometers were found to be flexible. Although both the specimens sintered under the same condition showed similar surface x-ray diffraction profiles with a strong accumulation of [110]tr orientation, the sintered C60 whiskers showed a higher micro-Vickers hardness and an electrical resistivity four orders of magnitude lower than that of the sintered C60 powder.

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.

Nanocrystallization of Cobalt Based Metallic Glass

2009 ◽  
Vol 67 ◽  
pp. 25-32 ◽  
Author(s):  
A.P. Srivastava ◽  
Dinesh Srivastava ◽  
K.G. Suresh ◽  
G.K. Dey
Keyword(s):  
Metallic Glass ◽  
Melt Spinning ◽  
Amorphous Ribbon ◽  
X Ray Diffraction ◽  
X Ray ◽  
Copper Addition ◽  
Isothermal Analysis ◽  
Effect Of Copper ◽  
Melt Spinning Technique

Effect of copper addition in a Metallic glass 2714A on the nanocrystallization characteristics have been examined in this study. Amorphous ribbon of the alloy composition Co64.5 Fe3.5 Si16.5 B13.5 Ni1Cu1 were prepared by melt spinning technique. Nanocrystallization kinetics was studied using differential scanning calorimeter technique. The kinetic parameters such as activation energy and Avrami exponent were determined using two different non-isothermal analysis methods. The kinetic behavior of individual crystallization event has been rationalized on the basis of these results. The role of addition of copper on the crystallization behavior has been understood by comparing with Metallic glass 2714A. The isothermally annealed nanocrystallized microstructures were characterized by X-ray diffraction.

scholarly journals Effect of Fe-Ni Substitution in FeNiSiB Soft Magnetic Alloys Produced by Melt Spinning

2021 ◽  
Vol 21 (4) ◽  
pp. 79-89
Author(s):  
Muhammed Fatih Kılıçaslan ◽  
Yasin Yılmaz ◽  
Bekir Akgül ◽  
Hakan Karataş ◽  
Can Doğan Vurdu
Keyword(s):  
Melt Spinning ◽  
Amorphous Structure ◽  
Soft Magnetic Materials ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
Sem Images ◽  
X Ray ◽  
Soft Magnetic Alloys ◽  
Fe Content ◽  
Rapid Solidification Technique

Abstract Alloys of FeNiSiB soft magnetic materials containing variable Fe and Ni contents (wt.%) have been produced by melt spinning method, a kind of rapid solidification technique. The magnetic and structural properties of FeNiSiB alloys with soft magnetic properties were investigated by increasing the Fe ratio. X-ray diffraction analysis and SEM images shows that the produced alloy ribbons generally have an amorphous structure, together with also partially nanocrystalline regions. It was observed that the structure became much more amorphous together with increasing Fe content in the composition. Among the alloy ribbons, the highest saturation magnetization was obtained as 0.6 emu/g in the specimen with 50 wt.% Fe. In addition, the highest Curie temperature was observed in the sample containing 46 wt.% Fe.

scholarly journals Fabrication of Porous Bone Scaffolds Using Alginate and Bioactive Glass

2019 ◽  
Vol 10 (1) ◽  
pp. 15 ◽  
Author(s):  
Jonathan Hatton ◽  
Graham Roy Davis ◽  
Abdel-Hamid I. Mourad ◽  
Nizamudeen Cherupurakal ◽  
Robert G. Hill ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Pore Size ◽  
Composite Scaffold ◽  
Average Pore Size ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Average Pore ◽  
X Ray ◽  
Novel Material

Porous composite scaffold using an alginate and bioactive glass ICIE16M was synthesized by a simple freeze-drying technique. The scaffold was characterized using compression testing, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), X-ray microtomography (XMT) and scanning electron microscopy (SEM). The bioactivity of the scaffold was evaluated by its ability to form apatite on its surface in simulated body fluid (SBF). The data collected showed evidence that the novel material produced had an appropriate pore size for osteoconduction, with an average pore size of 110 µm and maximum pore size of 309 µm. Statistical analysis confirmed that the glass filler significantly (P < 0.05) increased the collapse yield of the scaffolds compared with pure alginate scaffolds. The ICIE16M glass had an amorphous structure, favorable for bioactivity.

Structure Evolution of La(OH)3 /Fe Composite during Ball Milling

2020 ◽  
Vol 65 ◽  
pp. 123-134
Author(s):  
Samira Lalaoua ◽  
Bouguerra Bouzabata ◽  
Safia Alleg ◽  
Abedelmalik Djekoun ◽  
David Shmool
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
Magnetic Measurements ◽  
Amorphous Structure ◽  
Structure Evolution ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Composite Powders ◽  
X Ray

Fe-10wt% La (OH)3 composite powders have been fabricated by ball milling, under argon atmosphere for milling periods of 0, 5 and 10 h, respectively. Changes in structural, morphological, thermal and magnetic properties of the powders during mechanical alloying and during subsequent annealing have been examined by X-ray diffraction, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM). XRD results: showed the formation of new phases (Fe and LaFeO3 perovskite) created through the ball milling. The results showed that the crystalline size of ball milled powders decreased with increasing the milling time. In fact, after 10 h of ball milling, La (OH)3 changes from nanostructure in amorphous structure. The magnetic measurements display a distinct saturation magnetization and coercivity.

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