The antiphase domain magnetic structure of the DyGe3 compound

The effect of microstructure on the efficiency of shielding or shunting of the magnetic flux by permalloy shields was investigated in the present work. For this purpose, the FeNi shielding coatings with different grain structures were obtained using stationary and pulsed electrodeposition. The coatings’ composition, crystal structure, surface microstructure, magnetic domain structure, and shielding efficiency were studied. It has been shown that coatings with 0.2–0.6 µm grains have a disordered domain structure. Consequently, a higher value of the shielding efficiency was achieved, but the working range was too limited. The reason for this is probably the hindered movement of the domain boundaries. Samples with nanosized grains have an ordered two-domain magnetic structure with a permissible partial transition to a superparamagnetic state in regions with a grain size of less than 100 nm. The ordered magnetic structure, the small size of the domain, and the coexistence of ferromagnetic and superparamagnetic regions, although they reduce the maximum value of the shielding efficiency, significantly expand the working range in the nanostructured permalloy shielding coatings. As a result, a dependence between the grain and domain structure and the efficiency of magnetostatic shielding was found.

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Influence of the antiphase domain distribution on the magnetic structure of magnetite thin films

Applied Physics Letters ◽

10.1063/1.2356308 ◽

2006 ◽

Vol 89 (12) ◽

pp. 122517 ◽

Cited By ~ 20

Author(s):

J. D. Wei ◽

I. Knittel ◽

U. Hartmann ◽

Y. Zhou ◽

S. Murphy ◽

...

Keyword(s):

Thin Films ◽

Magnetic Structure ◽

Antiphase Domain

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Iron deficient BaNixMnxFe12−2xO19 (x = 0.0–0.5) hexagonal plates: single-domain magnetic structure and dielectric properties

Applied Physics A ◽

10.1007/s00339-020-03681-5 ◽

2020 ◽

Vol 126 (7) ◽

Author(s):

D. Chandra Sekhar ◽

T. Subba Rao ◽

K. Chandra Babu Naidu

Keyword(s):

Dielectric Properties ◽

Magnetic Structure ◽

Single Domain ◽

Iron Deficient ◽

Domain Magnetic Structure

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Nucleation of Disorder in Fe3Al Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061574 ◽

1967 ◽

Vol 25 ◽

pp. 312-313

Author(s):

P. R. Swann ◽

W. R. Duff ◽

R. M. Fisher

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Annealing Temperature ◽

Antiphase Domain ◽

Effect Of Temperature ◽

Domain Structures ◽

Transmission Electron ◽

Domain Boundaries ◽

Higher Temperature ◽

The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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Antiphase Boundaries in Ordered Ni3FE Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006221x ◽

1969 ◽

Vol 27 ◽

pp. 62-63

Author(s):

Y. H. Liu

Keyword(s):

Domain Size ◽

Antiphase Domain ◽

X Ray Diffraction ◽

X Ray ◽

Hardening Mechanism ◽

Superlattice Structure ◽

Disordered Phase ◽

Domain Boundaries ◽

Atomic Scattering ◽

The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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The observation of solutions in Ni3Nb

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104765 ◽

1988 ◽

Vol 46 ◽

pp. 540-541

Author(s):

Z.M. Wang ◽

J.P. Zhang

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Phase Modulation ◽

High Resolution Electron Microscopy ◽

Antiphase Domain ◽

Boundary Area ◽

Matrix Type ◽

Resolution Electron ◽

Domain Boundaries ◽

Kontorova Model

High resolution electron microscopy reveals that antiphase domain boundaries in β-Ni3Nb have a hexagonal unit cell with lattice parameters ah=aβ and ch=bβ, where aβ and bβ are of the orthogonal β matrix. (See Figure 1.) Some of these boundaries can creep “upstairs” leaving an incoherent area, as shown in region P. When the stepped boundaries meet each other, they do not lose their own character. Our consideration in this work is to estimate the influnce of the natural misfit δ{(ab-aβ)/aβ≠0}. Defining the displacement field at the boundary as a phase modulation Φ(x), following the Frenkel-Kontorova model [2], we consider the boundary area to be made up of a two unit chain, the upper portion of which can move and the lower portion of the β matrix type, assumed to be fixed. (See the schematic pattern in Figure 2(a)).

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Direct imaging of order-disorder and antiphase domain structures in Ti3Al intermetallic compound

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175533 ◽

1990 ◽

Vol 48 (4) ◽

pp. 480-481

Author(s):

H. Q. Ye ◽

T.S. Xie ◽

D. Li

Keyword(s):

Intermetallic Compound ◽

Volume Fraction ◽

Fundamental Problem ◽

Antiphase Domain ◽

Atomic Scale ◽

Orientation Relationships ◽

Domain Structures ◽

Α Phase ◽

Diffraction Patterns ◽

Two Phases

The Ti3Al intermetallic compound has long been recognized as potentially useful structural materials. It offers attractive strength to weight and elastic modulus to weight ratios. Recent work has established that the addition of Nb to Ti3Al ductilized this compound. In this work the fundamental problem of this alloy, i.e. order-disorder and antiphase domain structures was investigated at the atomic scale.The Ti3Al+10at%Nb alloys used in this study were treated at 1060°C and then aged at 700°C for 2 hours. The specimens suitable for TEM were prepared by standard jet electrolytic-polishing technique. A JEM-200CX electron microscope with an interpretable resolution of about 0.25 nm was used for HREM.The [100] and [001] projections of the α2 phase were shown in Fig.l.The alloy obtained consist of at least two phases-α2(Ti3Al) and β0 structures. Moreover, a disorder α phase with small volume fraction was also observed. Fig.2 gives [100] and [001] diffraction patterns of the α2 phase. Since lattice parameters of the ordered α2 (a=0.579, c=0.466 nm) and disorder α phase (a0=0.294≈a/2, c0=0.468 nm) are almost the same, their diffraction patterns are difficult to be distinguished when they are overlapped with epitaxial orientation relationships.

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