Iron-based Alloys Research Articles

The Environmental Friendly Modification of the Superhydrophobic Surface for Iron-Based Amorphous Alloy Films and Their Magnetic Surface Effect

The Environmental Friendly Modification of the Superhydrophobic Surface for Iron-Based Amorphous Alloy Films and Their Magnetic Surface Effect

Self-Prestressing Performance of Iron-Based Shape Memory Alloy Bars for New Structures

Self-Prestressing Performance of Iron-Based Shape Memory Alloy Bars for New Structures

Autowave description of the temperature effect during deformation of FCC metals

The data of comparative studies of the development of plastic flow in pure aluminum and iron-based austenitic alloy (Fe-Cr-Ni) are presented. Deformation patterns were studied during tests in the temperature range 143≤ T≤420 K. It was found that the effect of temperature is different for these two cases. When a stationary dissipative structure appears at the stage of parabolic strain hardening, the effect of temperature is determined by the change in the length of the localized plasticity autowave. At the stage of linear strain hardening, when a phase autowave of localized plasticity is formed, the effect is associated with an exponential increase in its rate with temperature. Keywords: plastic deformation, localization, metals, Debye temperature.

Автоволновое описание температурного эффекта при деформации ГЦК металлов

The data of comparative studies of the development of plastic flow in pure aluminum and iron-based austenitic alloy (Fe-Cr-Ni) are presented. Deformation patterns were studied during tests in the temperature range 143-420 K. It was found that the effect of temperature is different for these two cases. When a stationary dissipative structure appears at the stage of parabolic strain hardening, the effect of temperature is determined by the change in the length of the localized plasticity autowave. At the stage of linear strain hardening, when a phase autowave of localized plasticity is formed, the effect is associated with an exponential increase in its rate with temperature.

ELECTROKINETIC CHARACTERISTICS OF STRUCTURALLY DISORDERED BINARY ALLOY Ni1-xPx

The paper presents the results of studies of the temperature dependences of the resistivity ρ(T) and the Seebeck coefficient S(T) of binary structurally disordered alloys of the Ni1-xPx system. It was found that at 0.10 < x 0.18. The resistivity ρ increases with x, the temperature coefficient of electrical resistance α decreases and becomes negative, and S also increases and becomes positive near x=0.18. These results agree with the Mooij correlation and the r-S correlation for the studied samples, namely for samples with high resistivity S> 0 and for samples with low resistivity - S <0, which is observed in some non-magnetic structurally disordered alloys. Thus, the Ni1-xPx system covers the range and behavior of electrokinetic characteristics that are characteristic of a few structurally disordered alloys. For x <0.175 dependencies r(T) and S(T) of the studied samples are similar to those observed in ferromagnetic structurally disordered iron-based alloys.

Study of Structure and Properties Formation of Products, Obtained by Direct Laser Deposition, in Process of Plastic Deformation of Iron-Based Alloy

Study of Structure and Properties Formation of Products, Obtained by Direct Laser Deposition, in Process of Plastic Deformation of Iron-Based Alloy

OKMC simulation of matrix defect evolution of Fe-C Alloy under irradiation

The effects of carbon traps in Fe-C alloys on matrix defects and the evolutions of matrix defects in Fe-C alloys under irradiation are investigated in this paper. The object kinetic Monte Carlo (OKMC) modeling is used to establish a bridge between the micro-computational simulation data and the macro-experimental data. The simulation results verify the evolution of the carbon (C)-vacancy (Vac) complex under ideal conditions, and at relatively low temperatures, the complex is mainly C-Vac<sub>2</sub>. Under the assumption of complex traps, the evolution of matrix defects in Fe-C systems under irradiation is simulated in this work. It is verified that the carbon vacancy complex has an obvious trapping effect on matrix defects, and the simulation results of evolution simulation of matrix defects in the Fe-C system under irradiation are consistent with the experimental results. Furthermore, the effective approximate parameters used in the simulation are compared and discussed. The present research can provide a basic support for the research on the evolution of iron-based alloy irradiation defects.

Effect of heat treatment on structure and mechanical properties of dispersion-hardened iron-based alloys

The analysis of the structure and properties of dispersion-hardened iron-based alloys after various variants of heat treatment is carried out. The effect of various strengthening and reducing nanodispersed additives on the structure and properties of alloys after heat treatment is considered. Fractographic studies of the surface of investigated alloys after heat treatment, as well as metallographic studies to analyze the structure of materials are performed. The results can be useful in developing of method for manufacturing of increased mechanical properties products.

Численное и экспериментальное моделирование демпфирующих свойств материалов при трении

The article presents the results of a numerical and physical experiment of the determination vibration damping efficiency through the use of an iron-based alloy with magnetic properties (steel 01Al5Ti), alloy with thermoelastic martensieve (titanium nickelide) and widely used for the manufacture of steel drilling tools high quality steel 40CrNi2Mo. The mechanisms of vibration damping are considered and the selection various materials to assess the effectiveness of their damping is produced. According to the research results, it was revealed that vibrations caused by friction sliding on a monolithic abrasive, steel 01Al5Ti showed the highest efficiency compared to materials from other groups.

Hot-extrusion behavior of biodegradable Zn-Mg alloys

Magnesium, zinc and iron-based alloys are the potential candidates for biodegradable implant applications and the effect of secondary processing on the biodegradability of these materials is of interest and being studied extensively. The evolution of gaseous hydrogen in magnesium-based alloys and higher corrosion rate limits the usage of these alloys, whereas, on the other hand, iron alloy's corrosion rate is too slow and leaves bulky corrosion products. The corrosion rate of Zn is in between the Mg and Fe, make it a potential alternate material. In the present study, pure Zn and Zn-Mg alloys are cast to different weight proportions and subjected to hot extrusion at different temperatures viz: 100, 150, 200, 250 and 300 °C. No surface defects were observed during extrusion of Zn at all temperatures, whereas Zn-Mg alloys were found to exhibit surface cracks at all temperatures except 200 and 250 °C. The presence of longitudinal tensile stresses at the surface due to frictional forces and inappropriate temperatures resulted in the development of cracks. The extruded samples were found to have fine microstructure as observed through an optical microscope. The XRD studies revealed the presence of the Mg2Zn11phase. The hardness of Zn was observed to increase by 26% after hot-extrusion which was due to the extensive grain refinement during extrusion.

Effect of electrolysis parameters on corrosion resistance of extra-low carbon high silicon iron-based alloy

PurposeHigh silicon iron-based alloys possess excellent corrosion resistance in certain specific media, but the effects of electrolysis parameters on corrosion resistance remain unknown. This study aims to guide the development and application of an extra-low carbon high silicon iron-based alloy (ECHSIA) in electrode plates.Design/methodology/approachThe corrosion resistance of ECHSIA and a conventional high-silicon cast iron (CHSCI) was analyzed through experimental characterizations. The morphology was observed by scanning electron microscopy. The influence of electrolysis parameters on the corrosion resistance of ECHSIA was investigated through corrosion experiments. The relationship between the electrolysis parameters and the corrosion resistance of ECHSIA was statistically investigated using the grey correlation analysis method.FindingsThe corrosion resistance of the ECHSIA is better than that of the CHSCI. The corrosion rate showed an increasing tendency with the increase in the nitric acid concentration (CHNO3), electrolyte temperature and current density. The grey correlation analysis results showed that the CHNO3 was the main factor affecting the corrosion rate of the ECHSIA.Originality/valueAn ECHSIA with a single ferrite microstructure was prepared. This study provides a guideline for the future development and application of ECHSIAs as electrode plates.

Estimation of Energy Losses in Nanocrystalline FINEMET Alloys Working at High Frequency

Soft magnetic materials are at the core of electromagnetic devices. Planar transformers are essential pieces of equipment working at high frequency. Usually, their magnetic core is made of various types of ferrites or iron-based alloys. An upcoming alternative might be the replacement the ferrites with FINEMET-type alloys, of nominal composition of Fe73.5Si13.5B9Cu3Nb1 (at. %). FINEMET is a nanocrystalline material exhibiting excellent magnetic properties at high frequencies, a soft magnetic alloy that has been in the focus of interest in the last years thanks to its high saturation magnetization, high permeability, and low core loss. Here, we present and discuss the measured and modelled properties of this material. Owing to the limits of the experimental set-up, an estimate of the total magnetic losses within this magnetic material is made, for values greater than the measurement limits of the magnetic flux density and frequency, with reasonable results for potential applications of FINMET-type alloys and thin films in high frequency planar transformer cores.

Verification of Possibility of Molten Steels Decopperization with ZnAl2O4

In the previous research works, ZnAl2O4 material was considered as one of the solutions for the decopperization process of molten steels; up to 33% of decopperization efficiency was reported by utilising the ZnAl2O4 filter. In order to verify the decopperization possibility of ZnAl2O4 materials, iron-based alloys with various copper and carbon contents were interacted with ZnAl2O4 substrates in a heating microscope under an argon gas atmosphere at 1600 °C. Fe-Cu alloys were found to react with the ZnAl2O4 substrate during the interaction process, and a reaction layer with a complex composition around the alloy droplet was formed; however, Cu was not detected in the reaction layer. Cu was later found infiltrated inside of the ZnAl2O4 substrates. Furthermore, the Cu-Zn compounds were detected when the copper content in Fe-Cu alloys was 10 wt% Cu. After interaction experiments, copper was decreased in all cases. Thereby, the copper evaporation and infiltration into the ZnAl2O4 substrate were considered as the reasons for copper loss. Moreover, oxygen dissolved in melt was found to have a great effect on the copper evaporation process.

Combined Effect of Phosphate and Polymer Coating on Cytotoxicity and Hemocompatibility of Iron Foams

Abstract The use of resorbable metallic biomaterials for temporary implants has increased dramatically in the last decade. Degradable biomaterials are desirable in some specific pediatric, orthopedic, and cardiovascular applications, in which they may overcome the disadvantages of permanent devices. The three main biodegradable metals: Mg, Fe, and Zn, are intensively studied as temporary orthopedic implant materials. Among them, iron, and iron-based alloys, have received attention as promising materials for the temporary replacement of bones, especially for applications where strong mechanical support during the bone healing process is required. The addition of a low amount of phosphorus can improve the mechanical properties of such materials without the risk of retarding the corrosion rate or affecting cell proliferation. The main goal of this work was to study the combined effect of phosphating and polymer coating of open-cell iron foams on their cytotoxicity and hemocompatibility. Obtained results indicated the positive influence of the PEG coating layer and phosphorus addition on material cytocompatibility. Moreover, the combination of these procedures led to the inhibition of hemolysis, platelet adhesion, and thrombus formation.

Effect of Warm Compaction and Lubricant on Microstructure and Properties of Iron-Based Alloy

Effect of Warm Compaction and Lubricant on Microstructure and Properties of Iron-Based Alloy

Strength, plasticity, microhardness and inhomogeneous plastic deformation of strips made of amorphous multicomponent iron-based alloys

The structure of rapidly quenched ribbons from multicomponent iron-based alloys Fe81.4-Cr4.0-Mo6.0-Ni5.2-C1.0-Mn2.1-Al0.3, Fe71.7-Ni6.0-Co2.4-Cr7.5-Mo7.9-B4.0-Si0.5, Fe86-P9.8-C1.0-Si0.9-Al1.7-B0.6 has been studied by the methods of X-ray diffraction, X-ray phase and micro-Rhspectral analysis, and electron microscopy. It is shown that these materials are X-ray amorphous, and chemical elements are evenly distributed in them. Some physical and mechanical properties (strength, plasticity, microhardness) of amorphous multicomponent iron-based alloys have been experimentally investigated. It is shown that the alloy Fe81.4-Cr4.0-Mo6.0-Ni5.2-C1.0-Mn2.1-Al0.3; has the highest ductility; the highest strength and microhardness is the Fe71.7-Ni6.0-Co2.4-Cr7.5-Mo7.9-B4.0-Si0.5 alloy. Alloy Fe86-P9.8-C1.0-Si0.9-Al1.7-B0.6 is the most fragile, soft and fragile. It was found that the Fe81.4-Cr4.0-Mo6.0-Ni5.2-C1.0-Mn2.1-Al0.3 alloy has the highest inhomogeneous plasticity upon indentation of the surface by the Vickers pyramid. The features and regularities of inhomogeneous plastic deformation of multicomponent amorphous alloys based on iron at room temperature have been studied by the method of surface indentation. It is shown that two types of shear bands are formed at the indentation of the indenter on the surface of the amorphous ribbon: in the form of rays coming from the indentation, and in the form of rings bordering the indentation of the indenter. Under a load on the indenter of 1 N, the shear bands in the form of rays in the Fe71.7-Ni6.0-Co2.4-Cr7.5-Mo7.9-B4.0-Si0.5 alloy have the longest length, and shear bands in the form of rings in the Fe81.4-Cr4.0-Mo6.0-Ni5.2-C1.0-Mn2.1-Al0.3 alloy.

STRUCTURE AND PROPERTIES OF MELTED AREAS FORMED AT THE BORDER OF SECTION IN EXPLOSION WELDED JOINTS ALUMINUM-IRON-BASED ALLOY

The influence of the composition of iron-based alloys on the microhardness of the areas of the melted metal in explosion-welded joints with aluminum is investigated. It is shown that, other things being equal, the presence of chromium in the composition of an iron-based alloy leads to an increase in the hardness of the alloys by 1-2 GPa, and joint alloying with chromium and nickel, by 3 GPa.

Modification of metallic dispersions during high energy processing

The results of the authors’ own experimental studies in the current and promising scientific direction are presented – the study of the formation of the structure, crystal structure and properties of products obtained in the process of high-speed quenching from the melt of amorphizing iron-based alloys, attritor dispersion of metal fibers of amorphizing alloys after high-speed quenching of the melt and modification of metallic dispersions during pulsed laser processing. It has been shown that an important and urgent task of fundamental research on amorphous and nanocrystalline alloys obtained by ultrafast quenching from the liquid phase is the creation of new effective methods for targeted control of the geometry and quality of products with a microcrystalline and amorphous structure, based on the establishment of a functional relationship between the technological parameters of the created processes and the physical phenomena occurring during the shaping of products, and aimed at the creation of scientifically grounded technologies and highly efficient equipment for the production of a wide range of products and semi-finished products with specified properties for various purposes.

Accounting for Interelement Interferences in Atomic Emission Spectroscopy: A Nonlinear Theory

The article describes a nonlinear theory of how the presence of third elements affects the results of analyzing the elemental composition of substances by means of atomic emission spectroscopy. The theory is based on the assumption that there is an arbitrary relationship between the intensity of the analytical line of the analyte and the concentration of impurities and alloying elements. The theory has been tested on a simulation problem using commercially available equipment (the SPAS-05 spark spectrometer). By comparing the proposed algorithm with the traditional one, which assumes that there is a linear relationship between the intensity of the analytical line of the analyte and the intensities of the spectral lines (or concentrations) in the substance, it was revealed that there is a severalfold decrease in the deviations of nominal impurity concentrations from the measured ones. The results of this study allow for reducing the number of analytical procedures used in analyzing materials that have different compositions and the same matrix element. For instance, it becomes possible to determine the composition of iron-based alloys (low-alloy and carbon steels; high-speed steels; high-alloy, and heat-resistant steels) using one calibration curve within the framework of a universal analytical method.

STUDY OF THE TRIBOLOGICAL CHARACTERISTICS OF A POROUS IRON-BASED ANTIFRICTION ALLOY

The paper presents the results of a study of the tribological properties of an antifriction iron-based alloy with pyrite added to the charge under conditions of self-lubrication in comparison with an iron-graphite antifriction alloy.