The temperature dependence of the magnetization of rapidly quenched amorphous Fe–Ni–Si–B alloys was studied by the magnetometry method. The Curie temperatures were determined, and the exchange interaction parameters was calculated: the constants of spin-wave stiffness and exchange stiffness, the root mean-square range of the exchange interaction. The nearest neighboring distance between transition metal atoms was estimated based on the magnetic characteristics.

The temperature dependence of the magnetization of rapidly quenched amorphous Fe–Ni–Si–B alloys was studied by the magnetometry method. The Curie temperatures were determined, and the exchange interaction parameters were calculated: the constants of spin-wave stiffness and exchange stiffness, the root mean-square range of the exchange interaction. The nearest neighboring distance between transition metal atoms was estimated based on the magnetic characteristics.

A porous polymer loaded with segmented nanorods of magnetic metal is very promising for the design of novel microwave devices. Arrays of bi-segmented Ni/Co and core–shell Ni@Co rods were prepared by electroless deposition into porous of polycarbonate track-etched membrane. An intrinsic effective magnetic field of the magnetic composite nanorods aligned in the nonmagnetic template was studied by magnetization curves and ferromagnetic resonance (FMR). The effect of the interface boundaries for two types of bi-segmented rods with coaxial and along-axis Co/Ni segmentation to effective field was established.

Understanding the magnetic correlations in amorphous alloys is the key to enhancing their high soft magnetic properties. The magnetization correlations were studied in amorphous alloy ribbons Fe-Cu-Nb-Si-B by analysis of approach to magnetic saturation within the random magnetic anisotropy model. An unusual sequence of power laws during approach of the magnetization to saturation was observed. This may indicate the transition from isotropic to anisotropic magnetic correlations as the applied field decreases.

In this article, an alloy of the Finemet type Fe77Cu1Si16B6 obtained by quenching from a liquid state (spinning method) in the initial state is investigated. The main research methods were scanning and transmission electron microscopy. Methods for describing multiscale structural heterogeneities in amorphous-nanocrystalline alloys have been developed, allowing the structural state to be described and its influence on the physicochemical and technical properties to be determined depending on the technological conditions for obtaining these alloys. Representation of electron microscopic images in the form of Fourier spectra made it possible to reveal the nature of the formation of shortand middle-order in amorphous-nanocrystalline alloys according to the principle of selfsimilar spatial structures. The analysis of electron microscopic images by integral Lebesgue measures revealed density fluctuations over the alloy volume, which corresponds to the hierarchical representation of structural inhomogeneities in amorphous metallic alloys.

This paper presents a model of a thin film formation process of an amorphous alloy as a sequential procedure when a conditional unit of substance is randomly thrown onto a substrate at each next step. The islands of a precipitant are generated on the substrate with an increase of number of steps (density defects of substance). We determine the probability distribution of an island area, which shows the maximum informational entropy. An algorithm for computing estimates of parameters of this distribution is obtained. The results of processing experimental data are presented. We demonstrate that the proposed distribution is more consistent with the experimental data than the Pareto distribution.

A study is performed of rapidly quenched alloys of the Finemet type with different compositions. The Curie temperature, Bloch constant, critical exponent, and spontaneous magnetization at 0 K are calculated by analyzing the low- and high-temperature dependences of magnetization. A linear correlation is found between the constant of spin-wave stiffness and the Curie temperature.

Dependences of relative saturation magnetization on temperature are measured for amorphous nanocrystalline ribbons of Finemet-type FeCu 1 Nb 3 Si 13.5 B 8 , FeCu 1 Nb 3 Si 13 B 6 , and FeCu 1 Nb 3 Si 13 B 13 compositions. The character of the structural relaxation of amorphous alloys is established by means of Mössbauer spectroscopy, and the main magnetic characteristics are determined. It is found that the structural relaxation of amorphous ribbon proceeds in several stages upon annealing.

An understanding of the magnetic properties in an amorphous alloy requires comprehensive studies of magnetic anisotropy at various scales. In this paper such a study is carried out using amorphous ribbons FeCuNbSiB. The magnetic anisotropy associated with the rolling axis of ribbons does not affect hysteresis loop measurements, but the disappearance of a fingerprint-like pattern in the domain structure occurs in different fields when they are applied along and transverse the rolling axis. A correlation between the local magnetic anisotropy constant and the nanoscale within which the local easy axis is ordered was found.

The resonance microwave absorption in amorphous FeSiBNbCu ribbons with different compositions obtained by rapid quenching from the melt has been investigated. It is shown that the effective magnetization calculated from the resonance field linearly decreases with increasing boron and copper impurity concentrations and the total number of nonmagnetic impurity atoms in the iron-based FeSiBNbCu ribbons.

The results of a cross-correlation analysis of the relationship between the process conditions for obtaining CoNiFeSiB amorphous alloys, their physical and chemical properties and structure are presented. The alloys are obtained by single-roll rapid quenching on a copper wheel at frequencies from 30 to 60 Hz, which corresponds to linear velocities from 22 to 38 m/s, a chamber pressure from 0.05 to 0.6 atm, and a pressure in the crucible from 0.4 to 0.6 atm. Elemental analysis is carried out; the atomic and surface structures, phase-transition parameters upon heating, and the corrosion properties are investigated. Correlations between the structural-ordering parameters and physical and chemical properties are determined. Regression models of the dependence between the structural characteristics, physical and chemical properties, and process conditions of production are formulated. A regression model for the dependence of the average cluster area in the atomic image on the specific energy of structural changes is proposed. The concentrations of nickel, silicon, and boron in cobalt-based alloys are found to play an important role in determining the structural characteristics and properties of the alloys.

The structure of electrolytically deposited nanocrystalline alloys of the CoP-CoNiP systems under low-temperature heating was investigated by means of high-resolution transmission electron microscopy (HRTEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF STEM), and analytical methods such as energy dispersive x-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS). Structural relaxation and crystallization were investigated at temperatures from 150°C to 300°C. Structural and compositional inhomogeneities were found in the CoP-CoNiP alloys, while the local changes in composition were found to reach 15 at.%. Nanocrystals in the alloys grew most intensely in the presence of a free surface. It was determined that the local diffusion coefficient ranged from 1.2 to 2.4 10−18 m2/s, which could be explained by the surface diffusion prevalence. The data gathered in these investigations can be further used to predict the thermal stability of CoP-CoNiP alloys.

Magnetic properties of amorphous nanocrystalline alloy Fe–(Cu, Nb)–(Si, B) during stepwise annealing are investigated by means of X-ray diffraction analysis, vibration magnetometry, and Mössbauer spectroscopy. It is shown that an increase of the Nb content reduces the amount of the nanocrystalline component in the alloy, stabilizing the amorphous state and magnetic softness during structural relaxation.

We experimentally study the structure and dynamics of magnetic domains in synthetic antiferromagnets based on Co/Ru/Co films. Dramatic effects arise from the interaction among the topological defects comprising the dual domain walls in these structures. Under applied magnetic fields, the dual domain walls propagate following the dynamics of bi-meronic (bi-vortex/bi-antivortex) topological defects built in the walls. Application of an external field triggers a rich dynamical response: The propagation depends on mutual orientation and chirality of bi-vortices and bi-antivortices in the domain walls. For certain configurations, we observe sudden jumps of composite domain walls in increasing field, which are associated with the decay of composite skyrmions. These features allow for the enhanced control of domain-wall motion in synthetic antiferromagnets with the potential of employing them as information carriers in future logic and storage devices.

The aberration corrected transmission electron microscopy era inspires the development of new research methods. Due to small aberration many of HRTEM applications have become more precise and reliable. The research presented in this paper is devoted to developing a new method for revealing the 3D structure of thin films by focal series processing. We have obtained the sum of the Fourie power spectra in the sliding window of focal series images. Relative defocus value for the minimum of the power spectra is a target function depending on the thin film roughness. For amorphous CoNiP alloy films the new method shows roughness of up to 8 nm for site 65*65 nm in X, Y planes.