Nonferrous ore concentration
Melik-Gaikazian V.I., Emelianova N.P. Competitive representations in works on foam flotation and prospects of their application for selection of reagents
From positions of the experimental validity and utility in selecting reagents for foam flotation, five various representations are considered explaining the reasons of selective fastening of particles on bubbles. They are hysteresic, electrostatic, capillary, jointly radiographic and luminescent as well as sophistical representations, which were popular in the past, then rejected and now they are developed again, although they contain essential errors. The quantitative analysis of the representations allowed us to give preference to capillary one. This helped us to determine the influence of electric charge over particle surface (or ionic composition of pulp) on adsorption of neutral organic molecules being on it; to find out the nature of forces retaining particles on bubbles; to reveal a fluid layer between bubble and substrate; to determine the properties of thin fluid layers being the “glue” that retains particles on bubble; to find out the structure of boundary fluid layers adjoining solid and gas phases; to enter the quantitative criterion of non-equilibrium for characterizing the reagent properties manifesting in the dynamic conditions of foam flotation, and, mainly, basing on the capillary physics to expect various models of foam flotation for finding out of their mechanism and the reasons of existence; to find optimum conditions of solving specific tasks as well as the conditions of carrying reagentless and environmentally sound foam flotation. It is important also that the capillary representations allow us to note easily the primary inaccuracy not only of earlier popular (sophistical) hypotheses but also some modern ones.
Babich I.N., Adamov E.V., Panin V.V. The effect of pulp alkalinity on selective flotation of sulfide and oxidized copper minerals from ores of the Udokan deposit
The effect of one of the primary parameters of flotation concentration, i.e. pulp alkalinity, on the selective flotation of sulfide and oxidized copper minerals from ores of the Udokan deposit (Chita Region) has been investigated. It was found that pH = 9 for copper sulfide minerals and pH = 10 for oxidized minerals are optimal values. Lime and sodium sulfide supplying at the reduction stage into oxidized flotation cycle increases pH of pulp from 7 to 9 in the first case and from 8 to 10 in the second case, facilitating the increase of total copper extraction (from 84,2 % to 89,0 %) and selectivity (from 126,2 % to 161,3 %) of the flotation process.
Extractive metallurgy of nonferrous metals
Bychinsky V.A., Shepelev I.I., Golovnykh N.V., Didenkov Yu.N., Tupitsyn A.A., Chudnenko K.V. Investigation of methods to reduce sewage water from slime storages in underground and river waters by methods of physical-chemical activation of belite slimes
Using thermodynamic modeling, possible ways have been investigated to convert belite slime into mineral paragenesis stable under hypergene conditions, changing the physical structure of slime, and decreasing its filtering properties. It was found that decrease in filtering leaking can be attained at the cost of generation of clinker minerals (carboaluminates and tobermorite) that are formed with using micro-dispersed mud-injection agent (colmatant) prepared on the basis of amorphous silicon dioxide. Fine dust of silicon production from dry cyclones of gas-cleaning systems may be used as raw materials for production of mud-injection agents.
Extractive metallurgy of less-common and precious metals
Naumov A.V. World germanium market and its prospects
Based on the publications of the previous years, a review of the current state of the world germanium and germanium-containing product market after the 1999-2000 slack period was presented.
Casting production
Sidorov E.V. On equilibrium crystallization of three-component solid-soluble alloys
Equilibrium crystallization of continuous solid solutions in the three-component systems has been considered. It is shown that any three- and multicomponent alloy with unlimited component solubility in the liquid and solid state realizes the equilibrium crystallization like two-component one at the cost of diffusion decomposition of liquid and its diffusion interaction with the previously precipitated solid phase. The difference between the equilibrium crystallization process of the three- and multicomponent alloys and the two-component one is formation, at the temperature decrease at the cost of diffusion decomposition of liquid, nonequilibrium compositions of liquid and solid phases with maintaining the solid phase composition being equilibrium for the temperature before the decrease. The diffusion interaction of all the phase constituents leads to the formation of liquid and solid phases being equilibrium for the new temperature. Using graphic plotting and calculation it is shown that the three-component systems for some alloy compositions at definite crystallization steps may decrease the solid phase fraction as a result of diffusion interaction that is impossible for the two-component solid solution alloys.
Savchenko S.V., Koltygin A.V. Unstandardized technique of production of specimens for mechanical tests of cast aluminum alloys
An unstandardized technique of production of cast specimens is described for measuring the mechanical properties of aluminum alloys. For some time past, cast specimens are more and more widely used in the machine-building Industry; however as to the mechanical properties they do not satisfy the specimens turned from cast metal for the same alloy. In addition, their characteristics are strongly affected by the conditions under which the formation of cast structure of specimens takes place. The characteristic properties are considered as to interpretation of the results obtained for the specimens made according to the technique proposed and their conformity with the data, which are observed in using other methods of producing these products.
Materials science and heat treatment
Arisova V.N., Trykov Yu.P., Shmorgun V.G., Trudov A.F., Samarsky D.S. The formation pattern of diffusion layers in magnesium-aluminum composite
The results of metallographic investigations, micromechanical tests, X-ray structure analysis of the Al–Mg system laminated composite are given. It was found that intermetallic phases are not present in the contact area. Beginning at t =150 °C, local zones of diffusion layers are formed. Increase of holding time and temperature results in the growth of layer thickness (in the direction of Al) and their hardness (to 2–3 GPa at 150 °C for 1 h and to 4,5–5,0 GPa at 400 °C for 12 h). In holding for 16 h at 400 °C, the layer consists mainly of Mg2Al3 having hexagonal lattice.
Churyumov A.Yu., Solonin A.N., Zolotorevsky V.S. Simulation of yield stress in recrystallized single-phase alloys of the Al–Mg and Al–Cu systems
A model of the dependence of yield stress on alloying element concentration, grain size, and residual strain has been proposed for single-phase recrystallized alloys of the Al–Mg and Al–Cu systems. In analyzing alloy hardening mechanism, physical approach using showed similarity of yield stress dependences in different systems, allowing us to create a universal model for the alloys considered, the model giving the calculating error within 6 %.
Powder materials and coatings
Laptev A.I., Golovkov A.N., Kalantyra A.A., Polushin N.I. Study of interaction of silver-containing solders with composite material on the basis of dense forms of boron nitride
Being adhesive-active in respect to polycrystals on the basis of dense forms of boron nitride, solder of Ag–Cu–Sn–Ti composition has been developed. Strength tests, X-ray phase analysis of polycrystals, integrated metallographic and microradiographic spectral investigation of fracture zone in scanning electron microscope were carried out. It was found that solder with 10 % Ti content is optimal alloy. Optimal temperature of soldering is 950 °C.
Structural macrokinetics. Self-propagating high-temperature synthesis
Ovcharenko V.E., Lapshin O.V., Boyangin E.N., Ramazanov I.S., Chudinov V.A. High-temperature synthesis of intermetallic Ni3Al compound under pressure
The high-temperature synthesis of intermetallic Ni3Al compound was investigated by experimental and numerical methods at the conditions of thermal explosion under pressure of stoichiometric powder nickel and aluminum mixture. An analysis of design and experimental thermograph of SHS of intermetallic compounds as a function of preliminary heating temperature of powder mixture and external pressure was carried out.
Process control and automation
Rutkovsky A.L., Salikhov Z.G., Alyokhin V.I. On mathematical simulation of semiconductor electrolysis process
The mathematical models describing cathode processes that arise in the production of semiconducting materials are considered.
Economics and management
Andreev A.M., Kelchevskaya N.R. The effect of integration processes in nonferrous metallurgy for costs and prices at enterprises
The subject of research is the metallurgical industry of Russia. Being a very actual matter because of the necessity of improvement, the controlling mechanisms of cost and price level for metal products as well as the main directions of development of the nonferrous metallurgy and the nonferrous metal market are studied. Based on the results of the investigations of the main tendencies of the world and Russian nonferrous metallurgy, an analysis of these factors for costs and prices is made. The examples of the main institutional changes in the given industry of the RF are given. As a result, a procedure has been developed, which allows us to improve the controlling mechanisms of the cost and price level for metal products taking the situation in this field and in the nonferrous metal market into account.
