Extractive metallurgy of nonferrous metals
Trofimov E.A., Mikhailov G.G., Samoilova O.V. Thermodynamic analysis of interacting processes in the Pb–Ag–Zn system
The values of thermodynamic parameters have been determined for t = 325425 °С to permit calculating equilibrium compositions of liquid lead and their interconnected intermetallic phases in the Pb–Ag–Zn system. Using the thermodynamic calculations, the surface of component solubility in metal has been plotted for the system. The diagram can be used for analyzing the available literature data as well as for estimation of technological processes related to zinc to silver interaction in the lead melt. The calculation data are comparable to the experimental data.
Zaikov Yu.P., Arkhipov P.A., Plekhanov K.A., Ashikhin V.V., Khalimullina Yu.R., Khramov A.P. Anode dissolution of Pb–Sb alloys in equimolar mixture of potassium and lead chlorides
The effect of temperature and antimony concentration on the anode dissolution of the Pb–Sb alloys has been studied in the equimolar KCl–PbCl2 melt. Beginning at the potentials close to the equilibrium ones, lead dissolution is shown to be the main process under the certain current density. The calculation of the theoretical anode curve has been carried out in dissolving the Pb–Sb alloys. Mass transfer from Pb–Sb alloys is found to be the limiting stage.
Extractive metallurgy of less-common and precious metals
Voropanova L.A., Gagieva Z.A. Extraction of tungsten (VI) anions by sorption over AM2b grade macroporous anionite
The effect of pH, starting solution concentration, and preliminary sorbent processing on the results of sorption has been investigated. The effect of the polymerization processes on the kinetics of sorption and the sorption equilibrium has been considered.
Randin O.I., Afonina T.Yu., Dudarev V.I., Moskaeva N.Yu., Syrykh Yu.S. On the nature of active centers during sorption of cyanide complexes of precious metals over carbon sorbents
Using EPR spectroscopy, carbon sorbents produced from longflame coals of the LeninskKuznetsk coal field have been investigated. It is found that the sorption capacity of active coals in silver increases with a rise in paramagnetic center concentration, both parameters reaching the maximum at the activation temperatures of ~900 °С. The polyinterfaced aromatic system with a delocalized unpaired electron is proposed as sorbing surface.
Metal forming
Byvaltsev S.V., Zalazinsky A.G., Polyakov A.P. Experimentalanalytical method of composite damage calculation during extrusion
An experimentalanalytical method has been developed to study the stress and strain state and accumulation of damage of fibrous composite material (CM) components in the forming processes including the treating of experimental specimens of longitudinal and transversal metallographic sections of deformed CM. The prediction of material component damage was carried out with the use of the phenomenological theory of rupture. A software complex has been developed for the purpose of solving the tasks of plastic deformation of fibrous CM; the complex integrates the MATLAB computer mathematics system. Applying the ComposForm software complex, the process of fibrous CM extrusion has been investigated.
Casting production
Kats A.M. The effect of cooling conditions and physical properties of alloys on dispersion ability of dendrite structure of ingots and castings
It is found that an excess of dendritic cell dimensions in the steel structure as compared with Duralumin at the same of solidification rates is related to lower thermometric conductivity and higher temperature of steel crystallization (increased tendency to supercooling). In increasing the solidification rate, the dimension of a dendrite cell decreases because of prevailing effect of reduced crystallization time in the range of liquidus–solidus as compared with the supercooling growth action. Special actuality of increase in dispersivity of dendritic alloy structure has been observed while combining lower thermometric conductivity and higher crystallization temperature (steel, iron, nickel, nickel alloys).
Materials science and heat treatment
Mikhailovskaya A.V., Levchenko V.S., Sagalova T.B., Portnoi V.K. The effect of zirconium, chromium, and nickel additives on structure and superplasticity indices of the Al–Zn–Mg–Cu system alloys
Structure and properties of alloys of the Al–Zn–Mg–Cu system with Ni, Zr, and Cr additives during superplastic deformation have been investigated by light and transmission microscopy as well as Xray crystallographic analysis. Introduction of 0,26 % Zr is shown to result in formation of nonrecrystallized or partially recrystallized structure in stock materials. Such materials show the effect of superplasticity at t = 515 °С in a range of (0,151,0) · 10–2 с–1 in strain rate, elongation reaching 450–680 %.
Malkov A.V., Shevchenko V.V., Nizkin I.D., Lukianova E.V. Structure and properties of hot rolled bands produced from titanium chips without its remelting
Introduction of hydrogen technology allowed us to manufacture, by hot rolling, thin bands of VT10 titanium alloy chips without its remelting. It was found that plasticity of the bands is dependant significantly on availability of dispersed particles in excess in the structure. It is supposed that they are hardly soluble oxides formed during fracture in the course of shaping of oxide films retained on the chip surface. After homogenization, that may be combined with vacuum annealing for remove hydrogen, the structure and mechanical properties of the bands produced by the hydrogen technology comply with the characteristics of semiproducts produced by the ingot process.
Surface engineering. Multifunctional films. Corrosion and metal protection
Radyuk A.G., Titlyanov A.E., Strizhakova T.I., Kuznetsov V.E., Ukraintsev A.E. The effect of aluminum on nickel and chromium diffusion into copper during application and heat treatment of gasthermal coatings
Using Xray microanalysis, the distribution of elements has been investigated through the thickness of diffusion layer produced as a result of applying gasthermal coatings containing Al, Ni, Cr, Fe onto copper and the following heat treatment. It was found that the depth of penetration and the concentration of coating elements in copper reach maximum values in case of aluminum sublayer formation.
Baranov A.N., Gusevа E.A., Krasnoperov A.N., Pobedash A.S., Yudin A.N. Investigation of corrosion processes in aluminum production and development of new methods of metal protection
Anode rods, processing tool, gas cleaning equipment are intensively corroded in the electrolysis aluminum production. High corrosion rate of instrument and equipment in aluminacryolite melts has been found. Application of composite chromium coatings is proposed for reducing corrosion fracture of technological equipment and anode rods made of ferrous metals. Electrolysis gas purification from sulfur dioxide is possible according to the acid schematic with producing sulfurous acid but this is accompanied by active corrosion of equipment made of ferrous metal. A possibility of application of corrosion inhibitors, particularly oxazolidins, for protection of gascleaning St3steel equipment existing in aluminum plants is considered.
Process control and automation
Nemchinova N.V., Bychinsky V.A., Belsky S.S., Klets V.E. Basic physicalchemical model of carbothermic melting of silicon
Describing the Si production process, a base 4tank physicalchemical silicon melting process in oresmelting furnaces (OSF) has been developed with the use of “Selector” software complex. In developing the model, the method of successive reactors was used with application of known bases of the thermodynamic data; dynamic tanks being satisfactory to the main temperature zones of the OSF crucible, a matrix of the compositions of charge components with provision for consumption indices, lists of probable components of the system were determined; process balance scheme was drawn up. The results of solving the model are given for the tanks for specified temperature range in introducing 15 independent components. The developed thermodynamic model of Si melting is different from those developed earlier by introduction of considerable amount of impurity elements and it describes adequately the real process of silicon production in OSF.
Information
Pikunov M.V., Sidorov E.V. About N.A. Belovs book “Ternary and quaternary diagrams”
