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The problem of crystallization of a molten particle with an initial temperature equal to the melting point is investigated during convective heat exchange on the surface. The heat conduction equation is solved for a region with movable interphase boundaries, the law of movement of which is not known in advance. For small-sized particles, analytical expressions are obtained that describe the propagation of the crystallization front, and the crystallization time with indication of applicability limits. [ABSTRACT FROM AUTHOR]

We studied the formation of the domain structure as a result of the motion of a planar interphase boundary in the {001}-cut tetragonal PMN-PT crystals during cooling with oriented temperature gradient. The specialized heating/cooling stage was assembled for this purpose. Piezoresponse force microscopy was used to image the domain structure at the (001) and (010) surfaces of the samples with high spatial resolution, revealing a complex quasi-periodic domain pattern with a periodicity from 300 to 400 nm. [ABSTRACT FROM AUTHOR]

We investigated the effect of C content on the superplasticity of medium Mn steel through high-temperature tensile testing of Fe–7Mn-(0–0.35)C (wt%) steels at temperatures ranging from 490 °C to 720 °C with an initial strain rate of 1.0 × 10−3 s−1. Superplasticity became evident at 550 °C for C-added steels and at 634 °C for the C-free steel. As all the C-added steels exhibited the highest elongation at 650 °C, we conducted in-depth analyses using the specimens tested at 650 °C. The elongation significantly increased with increasing C content up to 0.20 wt%. The results of strain rate sensitivity, apparent activation energy, and microstructural observations indicated that the low elongation of the 0C steel was attributed to the occurrence of dislocation creep, whereas the high elongations of both 0.10C and 0.20C steels were due to the occurrence of grain boundary sliding. The 0.20C steel exhibited higher elongation than the 0.10C steel due to its smaller average grain size and a larger area of α/γ interphase boundaries compared to the 0.10C steel. Meanwhile, the elongation of the 0.35C steel was not significantly improved compared to the 0.20C steel, despite having a smaller average grain size. This was because the 0.35C steel had a lower area of α/γ interphase boundaries, which resulted from the higher γ fraction. We believe the optimal C content for enhancing the superplasticity of Fe–7Mn steel is approximately 0.20 wt%, considering the 0.35C_T steel requires an additional tempering process, and its elongation was comparable to the 0.20C steel.

In the presented work, the charge state of P(VDF-TeFE)/Si-based composites obtained on the basis of nano-Si with a size of 50 nm and micro-Si particles with a size of 50 μ m and P(VDF-TeFE) copolymer of polyvinylidenefluoride with tetrafluoroethylene from polar polymers, was investigated, the amount of filler and the effect of ionizing radiation on these properties were studied. It has been shown that the observed differences in the charge state parameters of P(VDF-TeFE)/Si composites obtained with nano- and micro-sized Si are due to the higher concentration of nanoparticles and, accordingly, the effective surface area in the composites obtained with nanosized Si, and the change in the mobility of relaxors due to the effects of construction and destruction processes that occur in the polymer matrix and at the interphase boundary after the effect of gamma radiation. The reason for the observed changes in the depolarization processes of polarized P(VDF-TeFE)/nano-Si composites after gamma radiation is the change in the ratio between the construction and destruction processes in the system. [ABSTRACT FROM AUTHOR]

Carbon fiber (CF) was coated with micro-fibrillated cellulose (MFC) using vacuum-assisted deposition in aqueous suspensions at concentrations of 0.1%, 0.2%, and 0.4%. The impact of distribution mesh configurations (DM arrangements) and fabric layer configuration on cellulose deposition was examined. Multiscale CF-MFC-Epoxy composites were created using resin infusion under flexible tooling, forming a 3D network of MFC between CFs that transferred stress and acted as a node at the intersection of 0–90 bundles. The addition of 0.1% MFC suspensions improved flexural properties, using no distribution media enhanced deposition and penetration efficiency, and drying stacked layers of CF fabrics improved load transference between them. This combination of parameters resulted in composites with a 16% increase in flexural modulus and 45% increase in flexural strength. [ABSTRACT FROM AUTHOR]

This paper reviews quantitative characterization via transmission electron microscopy (TEM) and its application to interfacial phenomena based on the results obtained through the studies. Several signals generated by the interaction between the specimen and the electron beam with a probe size of less than 1 nm are utilized for a quantitative analysis, which yields considerable chemical and physical information. This review describes several phenomena near the interfaces, e.g., clear solid–vapor interface (surface) segregation of yttria in the zirconia nanoparticles by an energy-dispersive X-ray spectroscopy analysis, the evaluation of the local magnetic moment at the grain boundary in terms of electron energy loss spectroscopy equipped with TEM, and grain boundary character dependence of the magnetism. The direct measurement of the stress to the dislocation transferred across the grain boundary and the microstructure evolution focused on the grain boundary formation caused by plastic deformation are discussed as examples of material dynamics associated with the grain boundary. Finally, the outlook for future investigations of interface studies, including the recent progress, is also discussed. [ABSTRACT FROM AUTHOR]

This article describes the experimental results of microstructure and phase composition of Bi32I-n41Sn27 alloy obtained by ultrarapid solidification from melt at the melt cooling rate of 105 K/s. Rapidly solidified Bi32In41Sn27 alloy is composed of the ε phase (BiIn) and γ phase (Sn4In) having a dispersed structure. The average value of chords dγ of random secants located on the cross sections of the γ phase and the average specific surface area of the interphase boundary Sε–γ formed by the ε and γ phases depend on holding time t of the foil at ambient temperature; their dependences are described by the equations dγ = 0.58 + 0.29lnt and Sε–γ = 2.9 – 0.43lnt. Microhardness Hμ of the Bi32In41Sn27 alloy foil monotonically increases with holding time at ambient temperature and reaches saturation. Subsequent isothermal annealing at 60°C leads to Hμ equaling the microhardness of bulk specimen obtained at average cooling rates of 102 K/s. The chemical compositions of the foil in the layer adjacent to the surface of the solidification unit and in the layer contacting the environment agree in the range of measurement error. The alloy foil has a microcrystalline structure. In the alloy foils, the sharp texture (0001) of the γ phase and the weak binary texture (211) + (112) of the ε phase are generated, which do not change upon annealing at 60°C for 2 h. The Bi32In41Sn27 alloy foil can be used as a solder alloy without harmful components (lead, cadmium, and others). [ABSTRACT FROM AUTHOR]

Strength and toughness are destined conflicts in traditional inorganic materials. Herein, we prepared a high-performance calcium-silicate-hydrate (C-S-H) based organic-inorganic composites, with a trace of sodium alginate (about 8 wt%). A 1.9-fold increase in flexural strength and a nearly 6.8-fold enhancement for work of fracture are achieved in the composites, and importantly, the elastic modulus is increased by 22.2 %. Here, flawless C-S-H gel devoid of obvious interphase boundary was formulated attributed to the intercalation of sodium alginate into the C-S-H layer, creating a hybrid bonding network of hydrogen bonds together with the ion complexation effect. Concurrently, sodium alginate is to establish an organic plasticizing zone, aiding in the mitigation of stress within cracks. Hence, our study overcomes the challenge of achieving a harmonious balance between strength and toughness, offering innovative pathways for advancing the development of high-performance organic-inorganic composite materials. Besides, the improvement mechanism proposed in this research provides a pristine and feasible methodology for strengthening and toughening of Portland cement-based materials. [ABSTRACT FROM AUTHOR]

Electrochemical properties of cationic complexes of supramolecular cavitands from the cucurbit[n]uril (CBns) family are studied. Based on the analysis of a complex of systematic data on these compounds, basic regularities characterizing their adsorption behavior are formulated, in particular, the extremely high surface activity and unusually wide adsorption potential region over which the adsorption layer structure is transformed upon changes of the electrode charge value and sign. The varying of concentrations of reactants involved in the complex-formation reaction (the cavitand and inorganic cation) in the studied systems is shown to change significantly the observed picture of adsorption phenomena. The comparative analysis of adsorption data for systems containing supramolecular complexes of cucurbiturils with different cations can back qualitative estimating of their strength constants. It has been established by example of systems containing inclusive complexes of the СВ7 cavitand with organic cation (the cation of 3,3′-diethylthiocarbocyanine iodide dye) and with organic molecules (super-tough complexes with 1-hydroxyadamantan and ferrocene, the strength constants K of 109–1010 М–1 by order of magnitude), that including of neutral organic molecule into the cavitand cavity does not prevent the formation of an exclusive complex with sodium cation and that such a complex is not formed in the presence of organic cation in the cavitand cavity. It was demonstrated by example of the cobaltocene(Сос)/cobaltocenium(Сос+) redox-system studied in the solutions added with СВ7 and СВ7-free ones that the formation of adsorption layer of the Сос+ ⊂ СВ7 supramolecular complex particles preceding an electrode process leads to changing of the electrode reaction rate and mechanism. [ABSTRACT FROM AUTHOR]

Results of molecular-dynamic simulation of structural changes in the surface layer of a design cell of a BCC-crystal under short-term high-energy action are presented. A spatial model where the temperature of the design cell is distributed in accordance with the solution of a linear problem of heat conduction makes it possible to detect disruption of surface layer continuity, including localization of excess free volumes in the form of spherical pores. Dimensions of these imperfections and the time of their existence differ during modeling of laser radiation with different energy density. Conditions are revealed for pore stability during the whole simulation period and a relationship between crystallographic orientation of the "solid – liquid" interphase boundary and sizes of pores formed is determined. [ABSTRACT FROM AUTHOR]

The evolution characterization of the α/β interphase boundaries of the isothermally compressed Ti–5Al–2Sn–2Zr–4Mo–4Cr with lamellar microstructure was carried out via electron backscatter diffraction (EBSD) and transmission electron microscope (TEM). The effect of the α/β interphase boundary evolution on the dynamic globularization was discussed, and the nucleation model for the β recrystallized grain at the cusp of α lath in the late stage of deformation in terms of the classic nucleation theory was established. The mean α/β interface deviation angle from Burgers orientation relationship (BOR) increased continuously up to 18.9° with the increasing strain from 0.1 to 0.5, which was dominated by the continuous dynamic recrystallization. Restoration of BOR between α and β phases at the strains of 0.7 and 0.9 occurred due to the occurrence of recrystallized α and β grains following BOR, which was rationalized by a nucleation model considering the stored energy of deformation provided the driving force for nucleation at the cusp of α lath. Loss of coherency of α/β interphase boundaries at a strain about 0.3 was responsible for accelerating the dynamic globularization of α lamellae since the energy of α/β interphase boundaries increased up to the maximum value when the non-coherent α/β interphase boundaries were formed. Restoration of coherency of α/β interphase boundaries due to the recrystallization nucleation in the late stage of deformation did not substantially affect the dynamic globularization since the α/α intraphase high-angle boundaries (HAGBs) were formed and the most α/β interphase boundaries were non-coherent. [Display omitted] • Evolution mechanism of α/β interphase boundary was clarified on the basis of experimental results and theoretical model. • Loss of coherency of α/β interphase boundaries led to acceleration of dynamic globularization of α lamellae. • Restoration of Burgers orientation relationship between α and β phases in the late stage of deformation was rationalized by nucleation of recrystallization. [ABSTRACT FROM AUTHOR]

The influence of the orientation of Ti–Al interphase boundary on the intensity of mutual diffusion, as well as the influence of its deformation of Ti at temperatures above the melting temperature of Al, were studied by the method of molecular dynamics. Zope and Mishin EAM potentials were used to describe interatomic interactions in the Ti–Al system. Three orientations of the boundary relative to the hcp Ti crystal were considered: , , and . It was found that the orientation of the interfacial boundary affects the intensity of diffusion in the Ti phase: Al atoms diffused more intensively into the titanium lattice at the orientation and less intensively at the and orientations. This influence of the orientation of the interphase boundary is associated with the probability of detachment of the Ti atom from the crystal–liquid interface and is determined by the difference in the energies of the Ti atoms in the aluminum phase and those built into the boundary of the crystalline phase. At the initial stage of mutual diffusion, the boundary between the crystal and liquid metal was observed to shift from the very interface between Ti and Al by two or three atomic planes into the aluminum phase—a thin layer of aluminum near the boundary remained in the crystalline state, repeating the crystal lattice of titanium. This is due to the fact that the Ti–Al bonds at the boundary are much stronger than the interatomic bonds in liquid aluminum. When studying the effect of elastic deformation on the intensity of mutual diffusion, it was found that, in almost all cases, the intensity of diffusion increases with tension and decreases with compression, which is associated with a corresponding change in the free volume, which largely affects the diffusion mobility of atoms. [ABSTRACT FROM AUTHOR]

The process of diffusion mixing at the aluminum-silicon interface in the case of two, four, seven, and ten atomic aluminum monolayers on the silicon (111) surface has been studied. The investigations were performed by the molecular dynamics simulations method using Large-scale Atomic/Molecular Massively Parallel Simulator package. Concentration and density profiles at the phase interface were analyzed to investigate the kinetics of mixing. The formation of a transient diffusion layer at the boundary of the liquid and crystalline phases is established. The melting of the phase interface was explained in the framework of the theory of contact melting. It is shown that diffusion mixing, which precedes contact melting, occurs at the level of atomic blocks (clusters), i.e. we can talk about the island nature of contact melting at the initial stage. The diffusion process was analyzed based on the theory of free volume in liquids. [ABSTRACT FROM AUTHOR]

Relevance of the research.The process of emulsification is widespread in industry both in the primary processing of hydrocarbons and in the final stages of production of marketable products. The organization of continuous production of stable emulsions in flow-type devices before their direct applicationis of particular interest. This approach significantly reduces the deviation of the mixture concentration from the given values, caused by settling. The transition from batch devices to continuous machines allows reducingas well the size and intensity of the equipment, with large-scale production, which in its turn facilitates transportation, reduces installation and repair costs. One of the most progressive methods of increasing the efficiency of emulsification is to conduct the process under the influence of mechanical vibrations of the ultrasonic frequency range. The main aim of the research is toestablish the influence of the inhomogeneous system parameters on the emulsification intensity under the complex effect of mechanical mixing and ultrasonic vibrations. Methods: analytical review of the results of ultrasound emulsification of inhomogeneous systems, analytical study of the propagation of vibrations of the ultrasonic range through a layer of a two-component emulsion, experimental study of emulsification of immiscible liquids under mechanical stirring in the field of action of ultrasonic vibrations. Results.The paper considers emulsification under conditions of mechanical mixing and exposure to ultrasonic waves. The authors have determined analytically the dependence of the emulsification intensity on the physicochemical properties of liquids, the composition of the mixture and the height of the emulsion layer. It is revealed that the appearance of zones with resonant mechanical vibrations for the greatest dispersion efficiency is observed provided that the distance between the ultrasound source and the free surface of the liquid is an integer number of half-wavelengths of mechanical vibrations in the emulsion. The dependences obtained were verified experimentally by emulsifying the «diesel fuel – water» mixture. Evaluation of the quality of the emulsion was carried out visually by the presence of continuous homogeneous zones in the volume of the system under consideration, as well as by the size of the particles of the dispersed phase, in photographs taken with a microscope.

Many experimental and first principles studies on precipitation hardening alloys show that segregation of elemental species to the matrix-precipitate interphase boundary (IB) reduces the boundary's energy. This segregation mechanism can thermally stabilize the microstructure against precipitate coarsening processes and allow for higher operating temperatures in structural applications. In this paper, we develop a phase-field modeling framework to describe IB solute segregation in ternary alloys. The interfacial thermodynamics is effectively described by defining an IB phase with a characteristic free energy-concentration dependence. Equilibrium for the IB phase is established via the parallel tangent plane construction, analogous to classical treatments for segregation to free surfaces and grain boundaries. Analytic steady-steady solutions elucidating the dependence of IB properties on bulk phase composition, temperature and model parameters are derived for a one-dimensional system. Analytic relations for the classical thermodynamic quantities–IB energy and relative solute excess–are derived and the Gibbs adsorption equation is shown to hold; therefore, predictions of the model can be compared with experiments and atomistic simulations. An application of the model is demonstrated for Zn segregation to Mg/Mg 2 Sn using representative IB parameters. A two-particle coarsening simulation of IB segregation is performed: the result demonstrates enhanced coarsening resistance of the ternary alloy relative to the binary alloy. [ABSTRACT FROM AUTHOR]

In our study, we have obtained a multicomponent MoVSbNbCeOx/SiO2 catalyst with high catalytic activity for oxidative dehydrogenation of ethane (ODE) to ethylene. To date, multicomponent MoVTe(Sb)NbOx catalysts, which have been intensively studied during the last years, were found as very promising for the ODE to produce ethylene. It was generally agreed that the MoVTeNbOx catalyst was more efficient than MoVSbNbOx. The major drawback of using Te‐containing catalysts is the presence of environmentally harmful, toxic tellurium, and its volatility during the catalyst preparation and catalytic reaction conditions. In our work, the Mo1V0.24Sb0.23Nb0.08Ce0.01Ox/50 wt. % SiO2 catalyst was prepared via the spray‐dry method of aqueous solutions of the starting components, followed by heat‐treatment in He at 350 and 600 °C. For comparative purpose, one of the best Te‐containing catalysts Mo1V0.3Te0.23Nb0.12Ox was also tested in this reaction under the similar reaction conditions. A comparison of the catalytic properties of Sb− and Te− containing catalysts at the reaction temperature of 400–450 °C illustrates for both catalysts relatively high catalytic properties for ODE. The yield of ethylene of ca. 74 % was obtained for these catalysts, which exceeds the best yield reported in literature for Sb‐containing catalysts. The two main phases – M1 and M2 were revealed by XRD in the Sb‐containing catalyst. Intergrowth between the crystals of M1 and M2 phases with the formation of the interphase boundary in the highly active and selective Sb‐containing catalyst can be proposed from HRTEM results. The nature of the active state in this catalyst is discussed. [ABSTRACT FROM AUTHOR]

The crystallography and chemistry of interfaces between austenite and ferrite in duplex steels control many important materials properties but remain poorly understood. In this study, we experimentally show that in an additively manufactured and heat treated duplex stainless steel, the majority of austenite-ferrite interfaces terminate on {111} A /{110} F planes, and this behaviour is more pronounced for rational interfaces with the Kurdjomov-Sachs orientation relationship. Interface segregation was found to be controlled by not only the interface crystallography but also the bonding properties of solute atoms. Solute elements showed higher interfacial excess at irrational interfaces. Furthermore, a heterogeneous distribution of selected solute elements in austenite-ferrite interfaces planes was observed. Our findings reinforce the importance and, in fact, necessity to consider five independent crystallographic parameters and chemical architecture of interphase boundaries for advanced control of mechanical and other critical properties in duplex materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Relevance of the research. Development and destruction of a steady compound of insoluble liquids are widely applied at all stages of life cycle of commercial hydrocarbons: from primary trade processing to deep processing of oil products. Intensification of both direct and inverse processes will allow reducing considerably the overall dimensions and metal consumption of necessary technology equipment that in its turn will facilitate transportation, reduce costs of mounting and repair. One of the most progressive methods of increasing efficiency of emulsifying is the process as a result of ultrasonic oscillations. The main aim of the research is to determine the impact of inhomogeneous system impact on emulsifying intensity within the ultrasonic oscillation field. Methods: general principles of propagation, reflection and interference of acoustic vibrations in liquid, experimental methods for research acoustic emulsification of immiscible liquids. Results. The paper considers the mechanism of creating emulsion in interference of two counter waves of the ultrasonic range on the boundary of initial liquids contact. It is revealed that the greatest efficiency of dispersion is observed in case of resonant influence. The authors have determined analytically the dependence of the intensity of mechanical oscillations impact on arbitrary point of the system formed by two immiscible liquids in case of ultrasound distribution in the direction, normal in relation to boundary of the section of phases. Comparison of the results of analytical and pilot studies showed that the discrepancy of data disparity makes less than 10 % that allows, with sufficient accuracy, applying the described calculation procedure to optimize the constructions of devices for emulsifying the non-uniform compounds.

It is well known that interfaces play an important role in determining the mechanical response of materials. This paper focuses on the transforming shape memory alloy NiTi and is aimed towards a better understanding of austenite-martensite interface structure (steps and dislocation arrays) and the determination of transformation stress corresponding to the translation of this interface. In the present work, we characterize the defect content at the cubic-monoclinic interfaces via the Topological Model. The defect-induced displacement fields are generated within the framework of the Eshelby-Stroh formalism and further improved with Molecular Statics simulations accounting for interactions at the atomic level. The resulting defect core disregistry fields are employed as input to a modified Peierls-Nabarro framework for evaluating the transformation stress. We applied the proposed methodology to the particular case of NiTi alloy single crystals of specific orientations and predicted the transformation stress levels in close agreement with experiments. Moreover, the short-range interactions of dislocation core disregistry fields are shown to be responsible for the experimentally observed non-Schmid behavior of transformation stress levels. Overall, the paper represents an effort to improve our understanding of shape memory materials considering theory, computer simulation and experiment. Image 1 [ABSTRACT FROM AUTHOR]

The structure, as well as the elemental and phase compositions of the diamond–matrix interface of a diamond tool for abrasive wheel dressing, manufactured using a new hybrid technology, are studied. This technology combines the thermodiffusion metallization of diamond with chromium and sintering of a matrix based on a WC–6%Co carbide powder mixture with copper impregnation in a single cycle of the vacuum furnace operation. During matrix sintering, the compact arrangement of chromium powder particles around the diamond grains and the screening effect of the copper foil form favorable conditions that ensure the thermodiffusion metallization of diamond. Scanning electron microscopy, electron probe microanalysis, X-ray phase analysis, and Raman spectroscopy show that a metallized coating chemically bound with diamond is formed on the diamond surface in temperature-temporal modes and sintering conditions. The coating consists of chromium carbide and a solid solution of cobalt in chromium, which provides durable diamond retention in the copper-impregnated carbide matrix. Herewith, the matrix structure and microhardness, excluding the regions adjoining the diamond–matrix interface, remain the same as a matrix of a carbide powder mixture sintered in the absence of chromium. Comparative tests of similar diamond dressers show the high efficiency of the hybrid technology of formation of diamond-containing composites for tool application. It is shown that the specific productivity of a dresser prototype fabricated using the hybrid technology was 51.50 cm3/mg when dressing a grinding wheel made of green silicon carbide, which is 44.66% larger than a similar indicator of the same type of check dresser formed using the traditional method. [ABSTRACT FROM AUTHOR]

The contact between a hot object such as the particles of a molten metal and a cool and relatively volatile fluid such as water likely takes place in metal casting, paper manufacturing industries, and nuclear reactors. The highly intensive and quick heat transfer caused by the contact may increase the pressure in the vapor film formed on a hot particle within a short period leading to the vapor explosion followed by a strong pressure wave in a vessel containing a volatile matter. The present study aims to provide a mathematical model for contacting between a small hot copper metal sphere and water and explain the effect of pressure change in water vessel on the vapor film radius, pressure inside vapor film, as well as the saturation temperature at the interface. In addition, it examines the results of vapor film growth and the internal pressure of the film for such a phenomenon in nuclear power plants with fuel rod coolant pressures ranged between 60 and 150 bar. The results of the extremely high pressures of the vessels indicated an increase in the pressure pulse inside the vapor film within a short period which raised the likelihood of vapor explosion. [ABSTRACT FROM AUTHOR]

The stability conditions for metal interlayers at the diamond/(Ti,W)C–WC–Co matrix interface have been grounded and the critical interlayer sizes have been obtained depending on the composition and structure of the composite. The results of the research can be used to develop the technology that ensures the existence of metal interlayers at the diamond/(Ti,W)C–WC–Co interface, which allows for the relaxation of the stress between the diamond particles and the matrix, ensures strong retention of diamond particles by the matrix, and increases the service life of products made of the diamond–(Ti,W)C–WC–Co composite. [ABSTRACT FROM AUTHOR]

Al 0.7 CoCrFeNi high entropy alloy (HEA) with a microstructure comprising strain free face-centered cubic (FCC) grains and strongly deformed sub-structured body centered cubic (BCC) grains was subjected to correlative nanoindentation testing, orientation imaging microscopy and local residual stress analysis. Depending on the geometry of BCC-FCC interface, certain boundaries indicated appearance of additional yield excursions apart from the typically observed elastic to plastic displacement burst. The role of interfacial strengthening mechanisms is quantified for small scale deformation across BCC-FCC interphase boundaries. An overall interfacial strengthening of the order of 4 G P a was estimated for BCC-FCC interfaces in HEAs. The influence of image forces due to the presence of a BCC-FCC interface is quantified and correlated to the observed local stress and hardness gradients in both the BCC and FCC grains. [ABSTRACT FROM AUTHOR]

In a polycrystalline γ-γ′ nickel-based superalloy, γ′ precipitates with a close-to-twin orientation relationship to their surrounding matrix (named T-type precipitates) are found in recrystallized grains located near specific unrecrystallized grains (named recovered grains). This type of γ/γ′ interface has not been reported in literature before. Inherited from the ingot conversion process, recovered grains are characterized by a high density of micrometric and close-to-coherent γ′ precipitates. Resulting from the interaction of the recrystallization front with the latter precipitates, the T-type precipitates appear to form onto the recrystallization front. The present paper details the crystallographic characteristics of the T-type precipitates. [ABSTRACT FROM AUTHOR]

It is shown that in ferromagnetic films with anisotropy inhomogeneous in thickness, an interphase boundary can be formed for certain values and directions of the magnetic field. This boundary has a stable magnetic configuration. It is oriented parallel to the film plane and separates the regions with different orientations of the magnetization. In an alternating magnetic field, the interphase boundary oscillates, which may be accompanied by a resonance. The field and frequency dependences of the components of the magnetic susceptibility tensor are determined. It is shown that the susceptibility coefficients at a resonance are extremely sensitive to the direction of the external magnetic field which can underlie the development of a highly sensitive sensor. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Physics of Metals / Uspehi Fiziki Metallov is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tracer self-diffusion of Co in a compositionally complex AlCoCrFeNiTi 0.2 alloy is measured using the radiotracer technique. The complex multi-phase microstructure (a mixture of BCC, B2, σ, and FCC phases in dependence of the processing conditions) is carefully analyzed to quantify the measured concentration-depth profiles in terms of volume and short-circuit diffusion contributions. The analysis allowed to determine the volume diffusion coefficients in the B2 phase and those along the high-angle B2/B2 grain boundaries (GBs). The absence of any "sluggishness" of diffusion in this alloy is unambiguously verified, both for volume and GB diffusion contributions. [Display omitted] [ABSTRACT FROM AUTHOR]

The Cr-rich precipitates at the interphase boundary in stainless steels not only lead to the sensitization, which further induces the intergranular corrosion and intergranular stress corrosion cracking, but also significantly deteriorate the ductility and toughness. In this work, the formation of Cr-rich precipitates at the interphase boundary in type 430 stainless steel was investigated from the perspective of austenite−ferrite transformation kinetics. Cyclic heat treatment was firstly conducted to reveal the kinetic mode of transformation behavior, i.e., local equilibrium or para equilibrium. Subsequently, interrupted quenching during continuous cooling was carried out, which illustrated clearly the relevance of the formation of interphase Cr-rich precipitates to the Cr enrichment adjacent to the interphase boundary as revealed by line scanning of energy dispersive spectroscopy (EDS). Finally, this enrichment of Cr was interpreted by DICTRA simulation, which is based on the determined kinetic mode for austenite−ferrite transformation. This work has, for the first time, established the correlation between the formation of interphase Cr-rich precipitates and the austenite−ferrite transformation kinetics.