scholarly journals Prediction of melting time of complex ferroalloys by physical and chemical modeling

2019 ◽  
pp. 205-214
Author(s):  
A.F. Petrov ◽  
I.R. Snihura ◽  
L.A Golovko ◽  
N.A. Tsyupa
Keyword(s):  
Interatomic Interaction ◽  
Ferroalloy Production ◽  
Melting Time ◽  
National Academy Of Sciences ◽  
Chemical Modeling ◽  
Method Of Calculation ◽  
Metal Melts ◽  
Composition Structure ◽  
Complex Ferroalloys ◽  
New Generation

The purpose of this work is to implement a new approach to the description of the duration of melting (dissolution) of complex new generation ferroalloys during the deoxidation and doping of a metal melt. This approach is aimed at developing a methodology and criteria for the quantification and accounting of the micro-heterogeneity of multicomponent metal melts and their prediction on such important for steelmaking production characteristics as the melting time of ferroalloys, the description of the inter-mine interaction, which allows a deeper understanding of the process. deoxidation and refining of steel. In the work, the approach developed in the Institute of Ferrous Metallurgy of the National Academy of Sciences of Ukraine to solve problems of modeling of non-conformities that relate the composition, structure and properties of melts is used in the work. It is based on the original concept of physicochemical modeling of the processes of interatomic interaction in melts and solutions, developed by E.V. Prihodko. According to it, metal melts are considered as chemically unified systems. Changing their composition affects the complex of physicochemical properties due to changes in the parameters of their electronic structure. The method of calculation of criteria (∆Zy and d), characterizing the degree of difference between the electronic and structural state of the melt, as a chemically unified system, from the mechanical mixture of their initial components and the parameter was used to evaluate and account for the influence of the micron homogeneity of the structure of the metal melts of ferroalloy production. ρl, which takes into account the cluster spin in metal melts. Using these criteria and the available experimental data, analytical dependences were obtained to calculate the melting time of complex (ma-manganese, vanadium, niobium and boromatic) ferroalloys of the new generation. This will allow them to evaluate their effectiveness of application, which is associated with the highest assimilation of the main elements that affect

scholarly journals Forecasting the physical and chemical and thermophysical properties of nickel-containing ferroalloys

2018 ◽  
pp. 336-348
Author(s):  
A.F. Petrov ◽  
O.V. Kuksa ◽  
L.A. Golovko ◽  
N.E. Khodotova
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
Heat Capacity ◽  
Interatomic Interaction ◽  
Model Parameters ◽  
Melting Points ◽  
National Academy Of Sciences ◽  
Iron And Steel ◽  
Nickel Chromium ◽  
Composition Structure

The aim of the work is to study the possibility of using integral and partial model parameters of interatomic interaction for the systematic study of the most important consumer properties of nickel ferroalloys used for alloying steel and alloys. In the work, a new approach developed at the Iron and Steel Institute of the National Academy of Sciences of Ukraine was used to solve the problems of predicting the properties of alloys, connecting the composition, structure and properties of melts. Using experimental data on the heat of melting, heat capacity, thermal conductivity, thermal diffusivity of ferronickel, ferroboron, ferromolybdenum, ferro-tungsten, ferrozirconium and other ferroalloys, equations were obtained which made it possible to estimate these properties in advance. Analysis of the experimental data showed that the density of liquid iron-nickel-chromium alloys and their melting points are closely related to the interatomic interaction parameters. Using the parameters of interatomic interaction and experimental data, equations were obtained to describe the dependence of the crystallization temperature, specific density, specific heat capacity, thermal conductivity of nickel-chromium-containing ferroalloys on the parameters of interatomic interaction. Using the above equations, model melting points and ferronickel densities (FN-5M) were estimated using model prediction. The developed semi-empirical models can be used to predict the properties of standard grades of ferroalloys both within a single grade and the entire range of ferroalloys. This allows you to evaluate the effectiveness of the use of ferroalloys at the main stages of steelmaking.

scholarly journals Development of composition and process of obtaining multicomponent ferroalloys

2020 ◽  
Vol 63 (10) ◽  
pp. 791-795
Author(s):  
V. I. Zhuchkov ◽  
O. V. Zayakin
Keyword(s):  
Main Product ◽  
Raw Materials ◽  
Ferroalloy Production ◽  
Service Characteristics ◽  
Physicochemical Processes ◽  
Metal Processing ◽  
Progressive Technology ◽  
Complex Ferroalloys ◽  
New Generation ◽  
High Degree

The main product of ferroalloy plants is standard ferroalloys. They often do not have all the necessary service characteristics and are not very suitable for metal processing in a ladle. The developing progressive technology of steelmaking is forced to adapt to the existing range of ferroalloys, the standards for which have not been updated for 50 years or more. In addition, in recent years, the sources and markets of ferroalloy raw materials have changed, and their quality and content of leading elements have decreased. This makes it difficult or excludes the possibility of obtaining ferroalloys according to existing standards. In this regard, the production of more efficient ferroalloys of a new generation is required, suitable for progressive processes in the developing areas of ferrous and non-ferrous metallurgy 795 and smelted from non-traditional types of domestic ore raw materials. These include complex or multicomponent ferroalloys containing, in addition to iron, two or more functional elements. Complex ferroalloys should be created in the most favorable combinations of component. It contributes to the necessary effective impact on the iron-carbon melt with a high degree of assimilation of useful elements in it. The creation of scientific foundations for the formation of new compositions of multicomponent ferroalloys with high consumer properties, and the development of physicochemical processes for obtaining these alloys from unconventional ore raw materials contributes to solving the problems of developing compositions of effective new generation ferroalloys and expanding the ore base of ferroalloy production. When using the developed method of designing the composition of complex ferroalloys using unconventional raw materials, melting technologies were developed; various alloys of the systems were obtained and applied on a laboratory and industrial scale: Fe – Si – Cr, Fe – Si – B, Fe – Si – Ba – Ca, Fe – Si – Al – Nb, Fe – Si – Ca – Mg, Fe – Si – V – Ca – Mn, Fe – Si – Al.

scholarly journals The role of taking into account the interatomic interaction in predicting the complex of structurally-sensitive properties of steels and alloys for special purpose

2018 ◽  
pp. 361-370
Author(s):  
I.R. Snihura ◽  
D.N. Togobitskaya
Keyword(s):  
Computational Models ◽  
State Parameter ◽  
Interatomic Interaction ◽  
Homogeneous System ◽  
Experimental Information ◽  
Structure Property ◽  
Chain Composition ◽  
Forecast Models ◽  
Composition Structure

The aim of the work is to identify the influence of the chemical composition of steels and special-purpose alloys on the formation of their physicochemical and structural-sensitive properties. This problem is solved by mathematical modeling of the inseparable chain «composition - structure – property» taking into account the parameters of interatomic interaction in the melt based on the concept of a directed chemical bond. A steel melt is considered as a chemically homogeneous system, and the state of the melts is expressed through a set of integral parameters, the main of which are: Zy - system charge state parameter (e); r - statistically average internuclear distance (10-1nm); tgα is a constant for each element, which characterizes the change in the radius of the ion as its charge changes. On the basis of experimental information on properties and using the parameters of interatomic interaction, computational models are proposed for predicting the properties of steels and alloys. The forecast models took into account the parameters of micro-inhomogeneity of steel, which ensured a high accuracy of the operational forecast. A comparative analysis of the results of steel melting with the corresponding calculations based on the JMatPro software package confirmed the effectiveness of using the interatomic interaction parameters as models. The proposed models for determining the melting of chromium-nickel steels are recommended for use with the content of basic elements Cr, Ni from 0 to 30%. The research results are recommended for use in industrial environments through the integration of the developed models in the process control system of steelmaking, which will contribute to the directed formation of the composition and properties of smelting products, as well as reducing energy costs.

scholarly journals The interrelation of the chemical composition and mechanical properties of constructional alloyed steels

2018 ◽  
pp. 328-335
Author(s):  
V.A. Lutsenko ◽  
E.V. Parusov ◽  
T.N. Golubenko ◽  
O.V. Lutsenko ◽  
O.V. Parusov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Chemical Composition ◽  
Relative Elongation ◽  
Interatomic Interaction ◽  
Alloying Elements ◽  
Structural Parameter ◽  
National Academy Of Sciences ◽  
Iron And Steel ◽  
European Standards

The aim of the work is to determine the content intervals of alloying elements in structural alloyed steels, which ensure the obtaining of mechanical properties and the conformity of rolled products to the requirements of European standards. The studies were conducted using a predictive model developed by the Iron and Steel Institute of the National Academy of Sciences of Ukraine, taking into account the full chemical composition of the steel. The regularities of changes in the interatomic interaction parameter on the number of alloying elements in the steel composition and its relationship with mechanical properties are revealed. The dependences of mechanical properties (tensile strength, relative elongation) on the chemical composition of steel are constructed through the physicochemical criterion – the average statistical distance between interacting atoms (structural parameter d). The interrelation between the chemical composition and mechanical properties of chrome-molybdenum structural steels has been established. It is shown that increasing the chromium content increases the tensile strength, and doping with molybdenum and vanadium increases the ductility of rolled products. It was determined that in order to guarantee compliance with the requirements of the ultimate strength (900-1100 MPa) and relative elongation (> 11%) for steel 31CrMoV9, the content of alloying elements should correspond to the following intervals: 2.42-2.62%Cr, 0.2-0, 23%Mo and 0.17-0.20%V. The results obtained make it possible to predict the mechanical properties of doped steel, depending on the actual chemical composition of the steel.

scholarly journals DEVELOPMENT OF RESEARCH OF CHEMISTRY OF COORDINATION COMPOUNDS IN V.I. VERNADSKY INSTITUTE OF GENERAL AND INORGANIC CHEMISTRY NAS OF UKRAINE: FROM THE 30'S TWENTIETH CENTURY(part1)

2021 ◽  
Vol 87 (11) ◽  
pp. 21-44
Author(s):  
Elena Trunova ◽  
Larisa Koval ◽  
Vasyl Pekhnyo
Keyword(s):  
Inorganic Chemistry ◽  
Coordination Compounds ◽  
Functional Materials ◽  
Complex Compounds ◽  
Biologically Active ◽  
National Academy Of Sciences ◽  
Significant Research ◽  
History Of ◽  
Composition Structure ◽  
The Individual

The review considers the main stages of development of the chemistry of coordination compounds at the Institute of General and Inorganic Chemistry. VI Vernadsky National Academy of Sciences of Ukraine on the occasion of the 90th anniversary of its founding. An overview of complex compounds of p, d, f-me­tals with different classes of ligands (inorganic and organic), features of their synthesis, study of the structure and properties of the obtained compounds, contains current material on the use of synthesized complexes to create functional materials for different purposes. Me­thods of synthesis have been developed, do­zens of new coordination compounds with derivatives of hydrazones, amines, azomethanes, and thiosemicarbazones have been synthesized and isolated in the individual state. Their composition, structure and physicochemical pro­perties are determined. The general regularities that take place in the process of comple­xation of metals with ligands, as well as factors influencing the composition, structure and physico­chemical properties of the obtained coordination compounds are established. For the long history of the Institute has accumulated a huge amount of material on the problems of modern coordination chemistry. Significant research in this area belongs to Ukrainian scientists who have worked long and fruitfully at the Institute: A.K. Babko, K.B. Yatsimirsky, Ya.A. Fialkov, I.A. Sheka, S.V. Volkov, N.A. Kostromina, and who created scientific schools, known not only in Ukraine but also abroad. To date, the attention of scientists of the Institute has shifted from classical monomeric to bigeteronuclear, polynuclear, multiligand complexes, which is primarily due to intensive research of new functional materials: optical and magnetic, biologically active substances, as well as effective adsorbents, chemical sensors, catalysts, catalysts, catalysts and biochemical processes.

scholarly journals Optimisation of chemical composition of high-strength structural steels for achieving mechanical property requirements

2021 ◽  
Author(s):  
Oleksandr Babachenko ◽  
Hanna Kononenko ◽  
Iryna Snigura ◽  
Nataliya Togobytska
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Chemical Composition ◽  
High Strength ◽  
Interatomic Interaction ◽  
Structural Steels ◽  
Integral Model ◽  
Model Parameters ◽  
National Academy Of Sciences ◽  
Iron And Steel

In addition to thermomechanical treatment, one of the main factors affecting the mechanical properties of steel is the chemical composition. The chemical composition may vary for a special high-strength low-alloy steel to meet certain mechanical property requirements. This work presents an approach, based on the method of physical-chemical modelling developed at the Z.I. Nekrasov Iron and Steel Institute of the National Academy of Sciences of Ukraine, to optimise the chemical composition of high-strength structural steels. The principle of this method is to describe the chemical composition of a melt by a complex of integral model parameters of interatomic interaction, characterising the chemical and structural state of the melt. The experimental data were analysed to obtain the regression model for mechanical properties based on the parameters of interatomic interaction. Finally, a multi-criteria optimisation method was applied to obtain an optimal set of microalloying elements which ensure the required mechanical properties.

Collaboration for the Future: The Summary of the Belarusian-Russian Scientific and Practical Conference “Designing the Future and the Horizons of Digital Reality”

2020 ◽  
Vol 63 (10) ◽  
pp. 154-159
Author(s):  
Yulia F. Nikitsina
Keyword(s):  
Applied Mathematics ◽  
National Academy Of Sciences ◽  
Russian Scientific ◽  
The Future ◽  
Interdisciplinary Synthesis ◽  
Scientific Practical ◽  
New Generation ◽  
Academy Of Sciences ◽  
Practical Conference

The Belarusian-Russian scientific-practical conference “Designing the Future and the Horizons of Digital Reality” is an outcome of long-term cooperation between scientists of the Institute of Philosophy of the National Academy of Sciences of Belarus, M.V. Keldysh Institute of Applied Mathematics, and the Institute of Philosophy of the Russian Academy of Sciences. The conference participants focused on the problems of digital transformation of social reality, the formation of a common scientific and technological space of the Union State of Russia and Belarus, the interdisciplinary synthesis of knowledge and the role of the theory of self-organization in these processes. The conference participants also raised the issues of modern management theory, artificial intelligence, strategies for ensuring global national security, new generation transport, and prospects for Eurasian integration.

scholarly journals Quantum-chemical modeling of hydrogen bonds in α-glycine

2019 ◽  
Vol 57 (1) ◽  
pp. 21-26
Author(s):  
Alyona A. Lysenok ◽  
◽  
Pavel A. Kalmykov ◽  
Nina I. Giricheva ◽  
Tatiana G. Volkova ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Hydrogen Atoms ◽  
Acceptor Interaction ◽  
Chemical Modeling ◽  
X Ray ◽  
Method Of Calculation ◽  
Donor Acceptor ◽  
Crystal Fragment ◽  
Stretching Vibrations ◽  
Oxygen Atoms

Quantum chemistry was used to simulate a fragment of α-glycine crystal consisting of 5 and 6 glycine molecules. The α-glycine crystal fragment model was constructed using X-ray diffraction data contained in the Cambridge Crystallographic Database (CCDC). Theoretical IR spectra were obtained. It was shown that in a fragment of a crystal, glycine molecules in zwitterionic form form N-H...O hydrogen bonds of different strength, which correspond to different frequencies of stretching vibrations νst (N-H) of the NH3+ group. Full optimization of glycine crystal fragments consisting of a small number of molecules, regardless of the method of calculation, leads to the agglomeration of the structure. The system forms the maximum possible number of the most durable hydrogen bonds, thereby lowering the overall energy of the system, which leads to disruption of the crystal structure of the fragment, distortion of the parameters of hydrogen bonds in the crystal, and, consequently, to an unsystematic shift in the frequencies of N-H vibrations. To avoid this process, further modeling was performed by partially optimizing the geometry of the crystal fragment, with the positions of heavy nitrogen atoms, carbon and oxygen atoms being fixed, and only the positions of hydrogen atoms involved in the formation of hydrogen bonds were varied. Using the DFT/B3LYP/6-311G** method, the energies of donor–acceptor interaction in a fragment of a crystal, as well as its oscillation frequencies, are calculated. The calculated frequencies are consistent with the three experimental frequencies in the indicated X-ray region. A comparison was made between the calculated and experimental frequencies of the stretching vibrations of the N-H group of the NH3+ group. According to the geometric characteristics of the HB and the energy of donor-acceptor interaction between the lone electron pairs of oxygen atoms and the *(N-H) loosening orbitals, it was found that the hydrogen bonds of N-H...O between molecules in one layer are stronger than between molecules in different layers of a crystal.

Finding the Right Problems: Some HREM Applications to Interfaces

1984 ◽  
Vol 42 ◽  
pp. 376-379
Author(s):  
D. Cherns
Keyword(s):  
Grain Boundaries ◽  
High Resolution Electron Microscopy ◽  
Boundary Structure ◽  
Atomic Structures ◽  
Grain Boundary Structure ◽  
Resolution Electron ◽  
Point To Point ◽  
The Right ◽  
New Generation ◽  
Better Than

The use of high resolution electron microscopy (HREM) to determine the atomic structure of grain boundaries and interfaces is a topic of great current interest. Grain boundary structure has been considered for many years as central to an understanding of the mechanical and transport properties of materials. Some more recent attention has focussed on the atomic structures of metalsemiconductor interfaces which are believed to control electrical properties of contacts. The atomic structures of interfaces in semiconductor or metal multilayers is an area of growing interest for understanding the unusual electrical or mechanical properties which these new materials possess. However, although the point-to-point resolutions of currently available HREMs, ∼2-3Å, appear sufficient to solve many of these problems, few atomic models of grain boundaries and interfaces have been derived. Moreover, with a new generation of 300-400kV instruments promising resolutions in the 1.6-2.0 Å range, and resolutions better than 1.5Å expected from specialist instruments, it is an appropriate time to consider the usefulness of HREM for interface studies.

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