Structure of Fe-Based Metallic Glass after Crystallization Process

2010 ◽  
Vol 163 ◽  
pp. 165-168 ◽  
Author(s):  
Ryszard Nowosielski ◽  
Rafał Babilas ◽  
Grzegorz Dercz ◽  
Lucjan Pająk
Keyword(s):  
Magnetic Properties ◽  
Metallic Glass ◽  
Structural Changes ◽  
Crystallization Process ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
After Effects ◽  
Transmission Electron ◽  
Saturation Induction

The work presents a crystallization process of Fe-based amorphous alloy by characterization of the influence of annealing temperature on structural changes and magnetic properties of Fe72B20Si4Nb4 metallic glass. The studies were performed on the samples in the form of ribbons and rods. Crystallization behaviour of the studied alloy was examined by X-ray diffraction (XRD) and transmission electron microscopy (TEM) methods. The studies of soft magnetic properties of tested material involved magnetic permeability, saturation induction, coercive field and magnetic after-effects measurements.

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.

Characterization of Structure and Mechanical Properties of MoSi2-SiC Nanolayer Composites

1993 ◽  
Vol 322 ◽  
Author(s):  
H. Kung ◽  
T. R. Jervis ◽  
J-P. Hirvonen ◽  
M. Nastasi ◽  
T. E. Mitchell
Keyword(s):  
Mechanical Properties ◽  
Structural Changes ◽  
Crystallization Process ◽  
Mechanical Response ◽  
Cross Sectional ◽  
Annealing Conditions ◽  
Transmission Electron ◽  
Layer Structures ◽  
Amorphous Structures

AbstractA systematic study of the structure-mechanical properties relationship is reported for MoSi2-SiC nanolayer composites. Alternating layers of MoSi2 and SiC were synthesized by DCmagnetron and if-diode sputtering, respectively. Cross-sectional transmission electron microscopy was used to examine three distinct reactions in the specimens when exposed to different annealing conditions: crystallization and phase transformation of MoSi2, crystallization of SiC, and spheroidization of the layer structures. Nanoindentation was employed to characterize the mechanical response as a function of the structural changes. As-sputtered material exhibits amorphous structures in both types of layers and has a hardness of 11GPa and a modulus of 217GPa. Subsequent heat treatment induces crystallization of MoSi2 to form the C40 structure at 500°C and SiC to form the a structure at 700°C. The crystallization process is directly responsible for the hardness and modulus increase in the multilayers. A hardness of 24GPa and a modulus of 340GPa can be achieved through crystallizing both MoSi2 and SiC layers. Annealing at 900°C for 2h causes the transformation of MoSi2 into the Cllb structure, as well as spheroidization of the layering to form a nanocrystalline equiaxed microstructure. A slight degradation in hardness but not in modulus is observed accompanying the layer break-down.

Preparation and Characterization of the Soft Magnetic FeCo-based Amorphous Alloy with Enhanced Magnetic Properties and Thermal Stability

2000 ◽  
Vol 644 ◽  
Author(s):  
Martin Hollmark ◽  
Victor Tkatch ◽  
Sergey Khartsev ◽  
Alex Grishin
Keyword(s):  
Thermal Stability ◽  
Magnetic Properties ◽  
Melt Spinning ◽  
Crystallization Process ◽  
Eutectic Reaction ◽  
Soft Magnetic ◽  
Differential Permeability ◽  
Thermal Stability Of ◽  
Melt Spinning Technique

AbstractA glassy structure was formed in the Fe40Co40P14B6 alloy by melt-spinning technique. The as-quenched 2-8 mm wide and 15-30 [.proportional]m thick ribbons exhibit good soft magnetic properties: the saturation magnetization of 1.45 T, the coercive force of 4 A/m and maximum differential permeability at 60 Hz of about 90000. The FeCo-based glass crystallizes via eutectic reaction into a mixture of an austenite and a b.c. tetragonal Fe3P-like phase similar to that of the well-known Fe40Ni40P14B6metallic glass, but at temperatures about 60 K higher than the latter. The evaluation of the thermodynamic and kinetic parameters of crystallization process brought us to the conclusion that the improved thermal stability of the Fe40Co40P14B6 glass is caused by the enhanced interfacial nucleus-glass energy.

Nanocrystallization of Fe-Based Amorphous Alloys Fe73.5Cu1Nb3Si13.5B9 by Yb-Doped Fiber Laser Overlapping Irradiation

2012 ◽  
Vol 482-484 ◽  
pp. 2365-2370 ◽  
Author(s):  
Qian Li Ma ◽  
Yong Bao ◽  
Guo Rui Zhang ◽  
Li Meng Yu ◽  
Ling Fei Ji ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Fiber Laser ◽  
Laser Irradiation ◽  
Soft Magnetic Property ◽  
Internal Diameter ◽  
Soft Magnetic Properties ◽  
External Diameter ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
Transmission Electron

The paper presents a laser irradiation method for rapidly fabricating Fe-based nanocrystalline alloys using Yb-doped fiber laser with a wavelength of 1070nm by overlapping irradiation of the heated areas. The samples are annular cores rolled with 20μm-thick and 3.2mm-wide belts of amorphous alloy Fe73.5Cu1Nb3Si13.5B9, which have internal diameter of 14 mm and external diameter of 20 mm. Every side of the samples is irradiated for 15 min by fiber laser. X-ray diffraction and transmission electron microscopy (TEM) are used for microstructure analysis and observation. The samples irradiated by a defocus beam with a diameter of 7.1mm through a lens have better soft magnetic properties than directly by an original collimating beam with a diameter of 6.7mm. The dimension of homogeneous ultrafine grains is about 10nm with a bcc α-Fe (Si), which is the foundation of the excellent soft magnetic property. Uniform laser irradiation and the appropriate laser power are necessary for optimum microstructure and soft magnetic properties.

Microstructure and Magnetic Properties of CoFeHfO Rich Nanocrystalline Thin Films Application for High Frequency

2007 ◽  
Vol 558-559 ◽  
pp. 975-978
Author(s):  
L.V. Tho ◽  
K.E. Lee ◽  
Cheol Gi Kim ◽  
Chong Oh Kim ◽  
W.S. Cho
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetic Properties ◽  
Rf Sputtering ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
Electrical And Magnetic Properties ◽  
Transmission Electron ◽  
Nanocrystalline Thin Films

Nanocrystalline CoFeHfO thin films have been fabricated by RF sputtering method. Co52Fe23Hf10O15 thin film is observed, exhibit good magnetic properties with magnetic coercivity (Hc) of 0.18 Oe; anisotropy fild (Hk) of 49 Oe; saturation magnetization (4лMs) of 21 kG, and electrical resistivity (ρ) of 300 01cm. The frequency response of permeability of the film is excellent. The effect of microstructure on the electrical and magnetic properties of thin film was studied using X-ray diffraction (XRD) analysis and conventional transmission electron microscopy (TEM). The results showed that excellent soft magnetic properties were associated with granular nannoscale grains of α-CoFe and α-Co(Fe) phases.

Synthesis and Characterization of Nano-Hexaferrites SrFe12O19 by Aqueous Solution Method

2011 ◽  
Vol 306-307 ◽  
pp. 404-409 ◽  
Author(s):  
Jian An Liu ◽  
Mei Mei Zhang ◽  
Yan Fei Zhang ◽  
Shu Jiang Liu
Keyword(s):  
Aqueous Solution ◽  
Magnetic Properties ◽  
Solution Method ◽  
Nano Particles ◽  
X Ray Diffraction ◽  
Nanometer Materials ◽  
Transmission Electron ◽  
Fast Synthesis ◽  
Aqueous Solution Method

Nano-hexaferrite SrFe12O19 has been prepared using the aqueous solution method. The structure and magnetic properties of SrFe12O19 have systematically been investigated by X-ray diffraction (XRD), Thermo gravimetric (TG), Fourier transform infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM), as well as Vibrating Sample Magnetometer (VSM). The XRD and TEM results showed that the samples are composed of SrFe12O19 nano-particles which are on average 70×50nm in dimensions when treated at 1200°C for 2 hours. The magnetic properties indicated that the saturation magnetization and the intrinsic coercivity were 48 Am2/kg and 506KA/m, respectively. The aqueous solution method is generally applicable to produce the nano-hexaferrite SrFe12O19 and is proved to be a promising method for fast synthesis of nanometer materials using nitrate.

Synthesis and Characterization of Structure Controlled Nano-cobalt Particles

2002 ◽  
Vol 755 ◽  
Author(s):  
Shiqiang Hui ◽  
Mingzhong Wu ◽  
Shihui Ge ◽  
Dajing Yan ◽  
Y.D. Zhang ◽  
...  
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Silica Coating ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Average Grain Size ◽  
Wet Chemical ◽  
Face Centered

ABSTRACTNanostructured cobalt particles with and without a ceramic coating have been synthesized using a wet chemical method. The structure and magnetic properties of synthesized powder were characterized using x-ray diffraction (“XRD”), high-resolution transmission electron microscopy (“HRTEM”), and a Quantum Design (SQUID) magnetometer. The cobalt nanoparticles are of either face-centered cubic (“fcc”) and/or hexagonally close-packed (“hcp”) crystalline structures. The average grain size is ∼14 nm for cobalt (either fcc or hcp) with an amorphous silica coating, and the average grain size is ∼9 nm for hcp cobalt and 26 nm for fcc cobalt without a silica coating. The effect of annealing temperature on grain size and magnetic properties are addressed.

scholarly journals Fabrication and characterization of Si1-xGex nanocrystals in as-grown and annealed structures: A comparative study

2019 ◽  
Author(s):  
Muhammad Taha Sultan ◽  
Valentin Serban Teodorescu ◽  
Jón Tómas Guðmundsson ◽  
Andrei Manolescu ◽  
Magdalena Lidia Ciurea ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
Self Assembly ◽  
Structural Changes ◽  
Nano Particles ◽  
Ambient Atmosphere ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Interface Characteristics ◽  
Order Of Magnitude

Multilayer structure comprising of SiO2/SiGe/SiO2 were obtained by depositing SiO2 layers using reactive direct current magnetron sputtering (dcMS), whereas, Si and Ge were co-sputtered using dcMS and high impulse power magnetron sputtering (HiPIMS), respectively. The as-grown structures subsequently underwent rapid thermal annealing (550 – 900 °C for 1 min) in N2 ambient atmosphere. The structures were investigated using X-ray diffraction, high-resolution transmission electron microscopy along with photoconductive analysis, to explore structural changes and constituent properties. It is observed that the employment of HiPIMS facilitates the formation of SiGe nano-particles (~ 2.1 ± 0.8 nm) in the as-grown structure, and that presence of such nano-particles acts as a seed for heterogeneous nucleation, which upon annealing results in formation of periodically arranged columnar self-assembly of core-shell SiGe nanocrystals. Consequently an increase in photocurrent intensity by more than an order of magnitude was achieved by the annealing. Furthermore, a detailed discussion is provided on strain development within the structures, the consequent interface characteristics and its effect on the photocurrent spectra.

scholarly journals Fabrication and characterization of Si1− x Ge x nanocrystals in as-grown and annealed structures: a comparative study

2019 ◽  
Vol 10 ◽  
pp. 1873-1882 ◽  
Author(s):  
Muhammad Taha Sultan ◽  
Adrian Valentin Maraloiu ◽  
Ionel Stavarache ◽  
Jón Tómas Gudmundsson ◽  
Andrei Manolescu ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
Self Assembly ◽  
Structural Changes ◽  
Ambient Atmosphere ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Interface Characteristics ◽  
Order Of Magnitude ◽  
Grown Structure

Multilayer structures comprising of SiO2/SiGe/SiO2 and containing SiGe nanoparticles were obtained by depositing SiO2 layers using reactive direct current magnetron sputtering (dcMS), whereas, Si and Ge were co-sputtered using dcMS and high-power impulse magnetron sputtering (HiPIMS). The as-grown structures subsequently underwent rapid thermal annealing (550–900 °C for 1 min) in N2 ambient atmosphere. The structures were investigated using X-ray diffraction, high-resolution transmission electron microscopy together with spectral photocurrent measurements, to explore structural changes and corresponding properties. It is observed that the employment of HiPIMS facilitates the formation of SiGe nanoparticles (2.1 ± 0.8 nm) in the as-grown structure, and that presence of such nanoparticles acts as a seed for heterogeneous nucleation, which upon annealing results in the periodically arranged columnar self-assembly of SiGe core–shell nanocrystals. An increase in photocurrent intensity by more than an order of magnitude was achieved by annealing. Furthermore, a detailed discussion is provided on strain development within the structures, the consequential interface characteristics and its effect on the photocurrent spectra.

Structure and Magnetic Properties Investigation of CoZr and CoZrN Thin Films

2013 ◽  
Vol 464 ◽  
pp. 83-88
Author(s):  
Jitendra Singh ◽  
Arvind K. Singh ◽  
Sanjeev K. Gupta ◽  
J. Akhtar
Keyword(s):  
Magnetic Properties ◽  
Film Thickness ◽  
Nitrogen Content ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
Film Properties ◽  
Composite Matrix ◽  
High Electrical Resistivity ◽  
Transmission Electron ◽  
Transmission Electron Microscope Study

nanocomposite [(Co91.5Zr8.5)- or CZN films has been prepared by reactive co-sputter deposition method. Nitrogen content plays key role to tune soft magnetic properties. Experimental observation shows that, non-magnetic nitrogen content enhances magnetization and reduces coercivity. The nanostructure is composed of Co nanoclusters embedded in CoN/ZrN matrix, revealed by high resolution transmission electron microscope study. The d-spacing of single Co nanocluster was found to be ~0.22nm corresponding to (002) phase of Cobalt. X-ray diffraction result is in agreement with cubic (400) and (622) phase of CoZr. High electrical resistivity ρs~108μΩ-cm attained corresponding to 16% N2content films. Hysteresis loop squareness depends on film thickness and coercivity squareness (S*)~0.84, obtained for ~250nm film thickness. A correlated composite nanostructure evolution is responsible for nitrogen induced magnetization and, suggests that film properties can tuned by controlling nitrogen content, in CoN/ZrN composite matrix.

Sign in / Sign up

Export Citation Format

Share Document