STRUCTURAL ANISOTROPY OF AMORPHOUS ALLOYS INDUCED BY MECHANICAL CREEP DEFORMATION

We have investigated atomic structure of a Fe81B13Si4C2 metallic glass after mechanical creep deformation. We determined the structure function and pair density function resolved for azimuthal angle using x-ray scattering and a two-dimensional detector. The results are analyzed by the spherical harmonics expansion, and are compared to the often-used simple analysis of the anisotropic pair density function determined by measuring the structure function along two directions with respect to the stress. We observed uniaxial structural anisotropy in a sample deformed during creep experiment. The observed macroscopic shear strain is explained in terms of local bond anisotropy induced by deformation at elevated temperature. The bond anisotropy is a “memory” of this deformation after load was removed. We showed that use of sine-Fourier transformation to anisotropic glass results in systematic errors in the atomic pair distribution function.

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Structural anisotropy of amorphous alloys with creep-induced magnetic anisotropy

Acta Materialia ◽

10.1016/j.actamat.2011.11.017 ◽

2012 ◽

Vol 60 (3) ◽

pp. 1278-1286 ◽

Cited By ~ 19

Author(s):

M. Ohnuma ◽

G. Herzer ◽

P. Kozikowski ◽

C. Polak ◽

V. Budinsky ◽

...

Keyword(s):

Magnetic Anisotropy ◽

Amorphous Alloys ◽

Structural Anisotropy ◽

Induced Magnetic Anisotropy

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Moment canting and structural anisotropy in amorphous alloys: experiments using synchrotron Mössbauer radiation

Journal of Non-Crystalline Solids ◽

10.1016/s0022-3093(01)00545-2 ◽

2001 ◽

Vol 287 (1-3) ◽

pp. 81-87 ◽

Cited By ~ 10

Author(s):

Quentin A. Pankhurst ◽

Neil S. Cohen ◽

Luis Fernández Barquı́n ◽

Mike R.J. Gibbs ◽

Gennadii V. Smirnov

Keyword(s):

Amorphous Alloys ◽

Structural Anisotropy

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Structural Modification in Amorphous Magnetic Alloys Under Thermotreatment

MRS Proceedings ◽

10.1557/proc-400-335 ◽

1995 ◽

Vol 400 ◽

Author(s):

Leonid V. Poperenko ◽

Mykola V. Vinnichenko ◽

Vasyl’ V. Vovchak ◽

Iryna V. Yurgelevych ◽

Sergei G. Zaichenko

Keyword(s):

Amorphous Alloys ◽

Angle Of Incidence ◽

The Novel ◽

Structural Anisotropy ◽

Magnetic Alloys ◽

Structural Modifications ◽

Principal Angle ◽

Observed Behaviour ◽

The Relationship ◽

Atomic And Electronic Structure

AbstractThe experimental results of research of structural modifications in amorphous magnetic alloys (AMAs) under thermotreatment obtained by angular and spectroellipsometric methods are presented and discussed. The ductile-brittle transition was observed for the ribbons of some 3d-metal-based amorphous alloys. The relationship between the principal angle of incidence φ0 and annealing temperature Ta of alloys was obtained for the ribbons of AMAs. The observed behaviour of φ0 is connected with appearance of the novel amorphous phase’s clusters inside the surface’s layers of alloys.The influence of melt’s overheating on the atomic and electronic structure of AMAs was studied. It was found that the increase of melt’s overheating temperature leads to the decrease of absorption index within the whole spectral range (ħω=0.5–4.38 eV). The structural anisotropy of AMAs and its changes after annealings were determined by reflectometric and ellipsometric measurements.

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Relaxation studies of amorphous alloys with creep induced magnetic and structural anisotropy

Scripta Materialia ◽

10.1016/j.scriptamat.2012.07.025 ◽

2012 ◽

Vol 67 (9) ◽

pp. 763-766 ◽

Cited By ~ 7

Author(s):

Pawel Kozikowski ◽

Masato Ohnuma ◽

Giselher Herzer ◽

Christian Polak ◽

Viktoria Budinsky ◽

...

Keyword(s):

Amorphous Alloys ◽

Structural Anisotropy ◽

Relaxation Studies

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AEM analysis of crystallization in Ti-based amorphous alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075142 ◽

1983 ◽

Vol 41 ◽

pp. 270-271

Author(s):

A.R. Pelton ◽

A.F. Marshall ◽

Y.S. Lee

Keyword(s):

Magnetic Properties ◽

Amorphous Alloys ◽

Amorphous Materials ◽

Isothermal Annealing ◽

Amorphous Matrix ◽

Nucleation And Growth ◽

Current Interest ◽

Amorphous Films ◽

Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

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Ion Beam Mixing of Ni-Ti Bilayered Thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118345 ◽

1985 ◽

Vol 43 ◽

pp. 290-291

Author(s):

A. K. Rai ◽

R. S. Bhattacharya ◽

M. H. Rashid

Keyword(s):

Crystal Structure ◽

Thin Films ◽

Amorphous Alloys ◽

Ion Beam ◽

Ion Bombardment ◽

High Energy ◽

Mixing Efficiency ◽

Ion Beam Mixing ◽

Enhanced Diffusion ◽

Binary Metal

Ion beam mixing has recently been found to be an effective method of producing amorphous alloys in the binary metal systems where the two original constituent metals are of different crystal structure. The mechanism of ion beam mixing are not well understood yet. Several mechanisms have been proposed to account for the observed mixing phenomena. The first mechanism is enhanced diffusion due to defects created by the incoming ions. Second is the cascade mixing mechanism for which the kinematicel collisional models exist in the literature. Third mechanism is thermal spikes. In the present work we have studied the mixing efficiency and ion beam induced amorphisation of Ni-Ti system under high energy ion bombardment and the results are compared with collisional models. We have employed plan and x-sectional veiw TEM and RBS techniques in the present work.

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