Extractive metallurgy of nonferrous metals
Mechev V.V. Autogenous process for processing of polymetalic raw materials
A new process is proposed of autogenous sulfide-raw-material smelting with deep depletion of slag with coal in a gas generator. Gases from the gas generator are used for producing element sulfur. The process has been tested in the experimental-industrial conditions.
Tarasov V.P., Miklushevsky V.V., Vatulin I.I., Kulifeev V.K. Thermodynamic analysis in the Li5AlO4¾ Al system
A rise in the scale of production and application of lithium is accompanied by increasing the volume of lithium-containing waste. Their processing to produce lithium metal is expedient to execute by aluminothermic reduction of lithium aluminates in vacuum where Li5AlO4 five-lithium aluminate, that has the highest lithium content (27,78 %), is used as the starting raw material. Using an integral version of the Knudsen cell in the high-temperature mass-spectrum analyzer, the lithium vapor pressure in the Li5AlO4- Al system was measured. The standard enthalpy and entropy of five-lithium aluminate were calculated using the results obtained experimentally. According to the thermodynamic calculations, the degree of Li5AlO4 reduction above 90 % under the conditions of process vacuum (~10 Pa) is possible at T > 1100 ° C.
Metallurgy of less-common and precious metals
Buchikhin E.P., Chekmarev A.M., Kuznetsov A.Yu. Processing of zirconium metal waste with producing construction materials. Part 1. Study of dissolution of zirconium metal in the “non-aqueous organic solvents ¾ chlorine” system
Oxidizing chlorination of zirconium metal has been studied in the environment of different organic solvents. Dissolving N,N¢ -dimethylformamide- chlorine system is most effective. The kinetic study of zirconium dissolving has been carried out in the N,N¢ -dimethylformamide- Cl2 system. The effect of impurities on chlorination process was investigated. The modes of non-aqueous chlorination to be applicable for obtaining different production zirconium-containing solutions were developed.
Miklushevsky V.V. Investigation of kinetic mechanisms of the process of thermal dissolution of lithium hydroxodialuminate
The kinetics of thermal decomposition of Li2O× 2Al2O3× 11H2O lithium hydroxodialuminate (LHODA) has been investigated using high-temperature installation with continuous record of sample mass loss. LHODA dehydration was found to take place in sequence (“piece-meal” water extraction into the gas phase), and the process proceeds in the kinetic range. Using the Erofeev-Kolmogorov equation, the apparent activation energy of the process was found: E = 42,7 kJ/mol. The apparent activation energy of the process determined with the use of non-isothermal investigation method (from the data of derivative analysis) was found to be 41,3 kJ/mol.
Casting production
Znamensky L.G., Kulakov B.A., Ivochkina O.V. Manufacture of plaster moulds using barbotage-ultrasonic treatment
Theoretical and technological foundations of barbotage-ultrasonic treatment of molding plaster mixtures are given. The equations describing the processes of gas inclusions in suspension under the effect of ultrasound and solidification of plaster mixtures are proposed. The process of barbotage-ultrasonic treatment of plaster mixtures for production of high-precision moulds with improved physical and mechanical properties in manufacture of critical profilecomposite castings was tested.
Metal Forming
Afanasiev V.K., Prudnikov A.N., Peretyatko V.N. Estimation of plasticity and resistance to deformation of hypereutectic piston silumin
Using the method of hot torsion, the diagrams of plasticity and resistance to deformation of hypereutectic piston silumin with content of 18 % silicon in cast, homogenized, and deformed states are plotted. It was shown that the interval of maximum plasticity for deformed state moves to lower temperatures (maximum plasticity at T ~ 450 ° C) as compared with cast and homogenized alloys (T ~ 550 ° C) and its range expands.
Shatalov R.L., Lukashkin N.D., Kokhan L.S., Panasyuk V.F., Shimanaev A.E. Improvement of the calculating procedure of band spreading during rolling. Report 1
The paper has studied theoretically and experimentally the effect of models related to band-to-roll contact, anisotropy of deformations in longitudinal and transverse directions, and contact friction on precision of calculation of band spreading during rolling. The procedure of spreading calculation is made more precise and some practical recommendations are given.
Physical Metallurgy and Heat Treatment
A collection of articles devoted to the 75-th anniversary of Prof. B.A. Kolachev
Vozdvizhensky V.M., Kolachev B.A., Vozdvizhenskaya M.V. Structural diagram of titanium alloys in annealed state
A structural diagram in coordinates of “structural aluminum equivalent of a -stabilizers and neutral reinforcers – structural molybdenum equivalent of b -stabilizers” is proposed on the basis of statistical analysis of the published data on b -phase quantity in annealed titanium alloys. The isophase lines allowing evaluating the b -phase amount in annealed titanium alloys are shown on the structural diagram. The classification of titanium alloys on their composition is made more correct. The equation to calculate the b -phase amount based on the mentioned structural equivalents is proposed.
Kolachev B.A., Ilyin A.A., Ryndenkov D.V. Mechanisms of solution hardening of a -titanium
The regularities of solid solution hardening of a -titanium by alloying elements were generalized on the basis of analyzing the published data. It was shown that solid solution hardening effects were described by Labush and Fleisher parameters in the best extent from the assumption that the interaction of solute atoms with screw dislocation was the main factor.
Kononov S.A., Lomberg B.S., Kolachev B.A., Nosov V.K. General principles of thermomechanical treatment in producing disk pressings for gas-turbine engines from high-heat-resistant nickel alloys
The general principles of thermomechnical processing of nickel superalloys were ascertained. They included the requirements to structure and properties of initial pressing rod, the substantiation of heating conditions prior hot deformation of rods and heat treatment of die-forging, the choice conditions of hot deformation and heat treatment, the regulation of cooling rates after deformation and during heat treatment, the requirements to the final quality control.
Egorova Yu.B., Ilyin A.A., Kolachev B.A., Mamonov A.M. Physical metallurgical foundations of the effect of hydrogen on machinability of titanium alloys by cutting
The physical-metallurgical principles of mechanical-hydrogen treatment of titanium alloys were reviewed. Their alloying with hydrogen was shown to allow one, on the basis of phase and structural changes, to form the structure of alloys to provide easy mechanical processing. Improvement of machinability of titanium alloys by turning might be due to a number of favorable effects: microstructure refinement, changes of phase composition, reducing flow metal stresses, strength, hardness and toughness, enhancing thermal conductivity of titanium alloys. The combined action of these factors leads to reducing deformation and fracture work, to decreasing heat build-up during cutting of titanium alloys with hydrogen additions of the optimal concentrations.
Kolachev B.A., Ilyin A.A., Bylov B.B. On mechanisms of the effect of hydrogen on fatigue strength of titanium alloys
The fatigue strength of titanium alloys enhances with increase of hydrogen at low concentrations, it reaches the maximum at certain content, and then decreases. Increase of the fatigue strength caused by hydrogen addition may be due to solid solution hardening, transformation of rough lamellar structure into fine-grain ones, formation of coherent hydrides into hydrogen-saturated solid solution under action of elastic stresses, hydrogen segregates on interphase boundaries that causes decreasing of microdistortions on the interphase layer and facilitates stress relaxation, makes fatigue crack nucleation more difficult. The hydrides in the starting metal and those precipitated from supersaturated solution under action of deformation reduce the fatigue strength.
Powder Materials and Coatings
Ulanovsky Ya.B., Krupennikov S.A., Levitsky I.A. Mathematical modeling of mass transfer at high-speed electron-beam evaporation of metals and deposition of vapors on moving band-substrate
A mathematical model of mass transfer has been developed for the case of high-speed electron-beam evaporation of materials and vacuum deposition of vapor on the moving band-substrate. When modeling, the relation binding the recoil momentum of evaporating atoms with pressure of saturated vapor was made more exact. A procedure of calculation of a lunule form that is generated on the melt surface in the process of evaporation has been developed. A criterion of applicability of the model of an isothermal cylindrical lunule for calculation of the diagrams of direction of vapor and radiation flows was obtained. Adequacy of the model is proved by comparison of design and experimental values of the factor of using vapor and condensate thickness distribution over the width of the band.
Structural Macrokinetics. Self-Propagating High-Temperature Synthesis
Shkoda O.A., Terekhova O.G., Gamolko M.V., Chlykh L.D. Pressing features of mechanically activated niobium and silicon powder mixture
The results obtained by pressing of mechanically activated mixture of 62,3 % Nb + 37,7 % Si are presented. A high rating planetary ball mill was used for mechanical activation. Activation time was from 1 to 120 min. Then the powder mixture was compacted and the porosity was measured. The compaction force was varied from 6 to 15 MPa, and the compaction time was from 15 to 120 s. The X-ray phase study was performed with DRON-2 installation. The specific surface of powder mixture after activation was carried out by BET method. The dependencies of porosity and the activation time showed some features of compaction, which are most probably related to formation of agglomerates in the mechanoactivation process, fracture and polydispersity of particles.
Process control and automation
Salikhov Z.G., Bekarevich A.A., Kiselev L.A. Algorithms to calculate temperature profile of calcinable material along the length of rotary tube furnace by methods of L.S. Pontryagin and R. BellmanCalculation algorithms were developed for the temperature profile of calcinable material depending on the length of a rotary furnace shell by method of L.S. Pontryagin and modified method of R. Bellman. Using the algorithms, the values of cited temperature profiles for the starting charge materials of three compositions are calculated in a special package of mathematical treatment.
Khadzaragova E.A. Optimal trajectories of development of technologically closed system of metallurgical production
A task to search optimal paths of development of technologically closed system in the sense of utility vector is considered. The structure of Pareto set is determined as a set of terminal points confined between the best points, which are identified by experts who appreciate the results of the system development. A structural technique of building the Pareto-optimal set was proposed at different distribution of target points with respect to the set of attainability.
Economics and Management
Garbuz D.N., Sirazutdinova Zh.A. Foundations of effective control of sales network 85
Ways to solve the main problems related to effective control of sales network are proposed. A thorough choice of business associates, development of the system of contractual relations of a manufacturer with the participants of the distribution channels, foundation of the system of stimulation of the participants of the channels, organization of effective promotion of products among the participants of the channels and to final customers, establishment of control of the participants of the channels from the direction of a customer were taken as a principle of the management solutions. The market of spring products taken as an example, application of the procedure of control of sales network was shown, and a calculation of stimulation system on the basis of discounts was given. The main trends of the further scientific-applied work to establish and control the marketing network of an enterprise are designated.
