Quantitative Analysis of Domain Structure and Rapid Search for New Materials for Permanent Magnets

2018 ◽  
Vol 60 (7-8) ◽  
pp. 544-547 ◽  
Author(s):  
Yu. G. Pastushenkov ◽  
K. P. Skokov ◽  
A. I. Zhukov
Keyword(s):  
Quantitative Analysis ◽  
Domain Structure ◽  
Permanent Magnets ◽  
New Materials

The new materials of the permanent magnets: A view

2021 ◽  
Vol 10 (10) ◽  
pp. 332-337
Author(s):  
Aniket Kumar ◽  
Shiva Sharma ◽  
Mohd Ahamad
Keyword(s):  
Permanent Magnets ◽  
New Materials

scholarly journals Structure of Alloys for (Sm,Zr)(Co,Cu,Fe)Z Permanent Magnets: First Level of Heterogeneity

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3893 ◽  
Author(s):  
Andrey G. Dormidontov ◽  
Natalia B. Kolchugina ◽  
Nikolay A. Dormidontov ◽  
Yury V. Milov
Keyword(s):  
Phase Composition ◽  
Quantitative Analysis ◽  
Chemical Composition ◽  
Permanent Magnets ◽  
Composition Range ◽  
Structural Phase ◽  
High Coercivity ◽  
Structural Components ◽  
Structural Formation ◽  
Hysteretic Properties

An original vision for the structural formation of (Sm,Zr)(Co,Cu,Fe)Z alloys, the compositions of which show promise for manufacturing high-coercivity permanent magnets, is reported. Foundations arising from the quantitative analysis of alloy microstructures as the first, coarse, level of heterogeneity are considered. The structure of the alloys, in optical resolutions, is shown to be characterized by three structural phase components, which are denoted as A, B, and C and based on the 1:5, 2:17, and 2:7 phases, respectively. As the chemical composition of alloys changes monotonically, the quantitative relationships of the components A, B, and C vary over wide ranges. In this case, the hysteretic properties of the (Sm,Zr)(Co,Cu,Fe)Z alloys in the high-coercivity state are strictly controlled by the volume fractions of the A and B structural components. Based on quantitative relationships of the A, B, and C structural components for the (R,Zr)(Co,Cu,Fe)Z alloys with R = Gd or Sm, sketches of quasi-ternary sections of the (Co,Cu,Fe)-R-Zr phase diagrams at temperatures of 1160–1190 °C and isopleths for the 2:17–2:7 phase composition range of the (Co,Cu,Fe)–Sm–Zr system were constructed.

Magnetic-domain structure of Nd2Fe14B permanent magnets

1998 ◽  
Vol 84 (6) ◽  
pp. 3267-3272 ◽  
Author(s):  
Yimei Zhu ◽  
M. R. McCartney
Keyword(s):  
Domain Structure ◽  
Permanent Magnets ◽  
Magnetic Domain ◽  
Magnetic Domain Structure

Magnetic Anisotropy of Sm(Co0.68Fe0.22Cu0.08Zr0.02)7.7 Ribbons Produced by Melt Spinning

2002 ◽  
Vol 17 (3) ◽  
pp. 648-652 ◽  
Author(s):  
A-Ru Yan ◽  
Zhi-Gang Sun ◽  
Baoshan Han ◽  
Bao-Gen Shen
Keyword(s):  
Magnetic Anisotropy ◽  
Domain Structure ◽  
Melt Spinning ◽  
Permanent Magnets ◽  
Dendritic Structure ◽  
Axis Orientation ◽  
Needle Size ◽  
Ribbon Plane ◽  
Field Parallel ◽  
Melt Spun

A high degree of texture was observed in melt-spun Sm(Co0.68Fe0.22Cu0.08Zr0.02)7.7 ribbons prepared by single-roller melt spinning at low wheel speed; their easy magnetization axis was parallel to the ribbon plane. Magnetization studies showed an obvious magnetic anisotropy and a 90% higher remanance in ribbons for the field parallel to the longitudinal direction (8.5 kGs) than that for the field parallel to the wide direction (4.4 kGs); this was attributed to a dendritic structure of needle-size grains (2–3 × 10–40 μm) with their long axis parallel to the ribbon plane. This texture allowed the development of a new process for producing anisotropic permanent magnets. The domain structure was studied by magnetic-force microscope. A highly ordered and strip-shaped magnetic domain structure was observed on the surface of the ribbons. This was due to the preference for tetragonal c-axis orientation parallel to the surface of melt-spun ribbons. We calculated the domain wall energy γ and critical single-domain particle size Dc of Sm(Co0.68Fe0.22Cu0.08Zr0.02)7.7 ribbons.

Phase transformations in rapidly solidified Nd33Fe77 alloy

1992 ◽  
Vol 50 (1) ◽  
pp. 56-57
Author(s):  
A. Zaluska ◽  
L.X. Liao ◽  
X. Chen ◽  
Z. Altounian ◽  
J.O. Ström-Olsen
Keyword(s):  
Phase Transformations ◽  
High Performance ◽  
Melt Spinning ◽  
Permanent Magnets ◽  
New Materials ◽  
Amorphous Precursor ◽  
Eutectic Melting ◽  
Subsequent Transformation ◽  
Fe Alloys ◽  
Rapidly Solidified

Nd-Fe alloys are important for high performance permanent magnets (usually in combination with B, C or N) and a knowledge of the metastable and stable phases of the system is necessary for the development of these new materials. An effective way to investigate such phases is by crystallizing an amorphous precursor.Amorphous ribbons of the binary alloy Nd33Fe77 were produced by melt-spinning. The phase transformations induced by heat treatment of the as-quenched ribbons is complex involving first the production of metastable phases followed by subsequent transformation into stable phases and finally eutectic melting.

scholarly journals Quantitative analysis of the direct piezoelectric response of bismuth ferrite films by scanning probe microscopy

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kento Kariya ◽  
Takeshi Yoshimura ◽  
Katsuya Ujimoto ◽  
Norifumi Fujimura
Keyword(s):  
Quantitative Analysis ◽  
Domain Structure ◽  
Scanning Probe Microscopy ◽  
Domain Walls ◽  
Piezoelectric Properties ◽  
Bismuth Ferrite ◽  
Scanning Probe ◽  
Piezoelectric Response ◽  
Probe Microscopy ◽  
Piezoelectric Force Microscopy

AbstractPolarisation domain structure is a microstructure specific to ferroelectrics and plays a role in their various fascinating characteristics. The piezoelectric properties of ferroelectrics are influenced by the domain wall contribution. This study provides a direct observation of the contribution of domain walls to the direct piezoelectric response of bismuth ferrite (BiFeO3) films, which have been widely studied as lead-free piezoelectrics. To achieve this purpose, we developed a scanning probe microscopy-based measurement technique, termed direct piezoelectric response microscopy (DPRM), to observe the domain structure of BiFeO3 films via the direct piezoelectric response. Quantitative analysis of the direct piezoelectric response obtained by DPRM, detailed analysis of the domain structure by conventional piezoelectric force microscopy, and microscopic characterisation of the direct piezoelectric properties of BiFeO3 films with different domain structures revealed that their direct piezoelectric response is enhanced by the walls between the domains of spontaneous polarisation in the same out-of-plane direction.

Surface domain structure and local demagnetizing field in NdFeB permanent magnets

1994 ◽  
Vol 142 (1) ◽  
pp. K41-K45 ◽  
Author(s):  
Yu. G. Pastushenkov ◽  
L. E. Afanasieva ◽  
R. M. Grechishkin
Keyword(s):  
Domain Structure ◽  
Permanent Magnets ◽  
Demagnetizing Field
Sign in / Sign up

Export Citation Format

Share Document