MINERAL PROCESSING OF NONFERROUS METALS
Bocharov V.A., Ignatkina V.A., Alekseichuk D.A.
The effect of mineral composition of sulfides and theirmodifications on selection of scheme and collectors of selective flotation ofnonferrous metal ores
The effect of mineral composition of sulfides and theirmodifications on the selection of schemes and collectors for selectiveflotation of nonferrous metal ores is considered. It is shown that in themechanism of interaction of collectors with minerals the conditions of theiroxidation with formation of new forms of the collector participating information of sorption layers on the surface are of importance. As practicalstudies have shown, application of various collector composition combinationsallows increasing their collective and selective properties and improving theefficiency of mineral flotation separation. Experience has shown that theadsorption layer structure when using collector compositions (one of which isxanthogenate) in flotation is determined by a ratio of components and sequenceof their dispensing. The obtained results allowed us to modify the flotationschemes of ores from the Tarnersky, Gaisky, and other deposits with extractionof pyrite and false galenite modifications by the stages flotation process.
Key words: flotation,collector, sorption, mineral, flotation agents, ore, collectorcomposition, agent, surface, adsorption layer.
METALLURGYOF NONFERROUS METALS
KirovS.S., Nikolaev I.V., Zakharova V.I., Bogatyryov B.A., Magazina L.O.
Combined method of processing high-silicon boxites - partiallylateritic condalites
The results of processing high-silicon aluminum raw materials -partially lateritic condalite from the Panchmatmali deposit (India) according to the two-stage scheme of Bayer-hydrochemistry with processing of red mudaccording to the hydrogarnet process are presented. In processing Bayer-leg redslurry, silicon removal is carried out through ferrous hydrogarnet when anactive additive of iron oxide in the form of sodium ferrite is introduced. Theoptimum conditions of leaching red slurry are found: temperature is 235–250 °C,alkali concentration 250 g/dm3, caustic module 26,6, quantity ofactive iron oxide is stoichiometric with an eye to ferrous hydrogarnetformation of 3CaO·Al2O3·2SiO2 composition.Losses with ferrous residue amounted to 4 % for sodium oxide and 5 % foraluminum oxide. The solid phase is identified with JSM-5610LV scanning digitalelectron microscope and D/Max2000/PC series diffractometer («Rigaku», Japan).
Key words: Indian condalite, leaching,red slurry, sodium hydroalumosilicate, ferrous hydrogarnet, aluminumhydrogarnet, minimization of sodium and aluminum oxides losses.
METALLURGY OF LESS-COMMON AND PRECIOUS METALS
Yermakov A.V., Naboichenko S.S.
Iridium: production, consumption, prospects
Trends in increasing the use of high-pure iridium and its alloys indifferent branches of the industry and medicine are shown. Application ofiridium (wire, rings, tubes, disks et al) is described. The data for the effectof impurity elements on technological, operating, and mechanical properties ofiridium are given. The improvement of the product quality can be reached afterrefining iridium by electronic-beam smelting and plastic deformation.
Key words: iridium, application,allowing, service durability, interstitial impurities, alloys with iridium.
Dyakov V.E.
Investigation of indium extraction with salt melt from waste metal
The research of indium extraction kinetics by zinc chloride moltensalt out of lead-tin alloys and the effect of molten salt composition have beencarried out. The dependence of the positive effect of ammonium chloride andlead chloride on the indium extraction process kinetics out of metallic meltinto molten salt is found. The results of investigations made can be used inthe development of an industrial method and apparatus for indium extraction outof lead-tin alloys and secondary waste.
Key words: indium; waste products ofalloys; zinc, lead, ammonium chloride molten salts; kinetics; extraction;effect of zinc and arsenic impurities.
CASTINGPRODUCTION
BazhenovV.E., Pashkov I.N., Pikunov M.V.
Study crystallization processes in soldering copper withcopper-phosphoric solder for the purpose of soldered seam structure control
The possibility of forecasting the brazed seam structure isconsidered. Brazing temperature is taken as the main way of influence becausefor eutectic systems the liquid brazing alloy composition in the seam isdefined by the liquidus line of the «brazing solder – material to be brazed»equilibrium diagram. The effect of non-equilibrium conditions ofcrystallization on the brazed seam structure has been studied. It isinsignificant for the Cu-P system because of small change of the phosphorussolubility in the solid phase in the course of crystallization. A simpleformula for definition of brazed seam thickness is proposed. The results ofcalculations are confirmed by the experiments of brazing copper withcopper-phosphoric brazing solder. It is shown that any content of eutectic inbrazed seam can be obtained and hence one can vary strength properties of theseam.
Key words: binary system diagram,non-equilibrium crystallization, braze solders, Cu-P system brazing solders.
Drokina V.V., Belov V.D.
Investigation of cast and mechanical properties of AK8L alloy incastings produced with using printed mold boxes made of ZCAST mixture
In view of lacking of the data for casting and mechanical propertiesof AK8L alloy in casting into printed mold boxes made of ZCast mixture,investigations have been carried out for determination of alloy runningquality, segregation, and mechanical properties as well as increasing relativeelongation of the alloy by optimization of its chemical composition. Thecasting method into printed mold boxes made of ZCast mixture is shown to beable to be used effectively in the production of essential castings of AK8Lalloy, especially at the stage of preparing the production of cast products.
Key words: prototyping,three-dimensional print, mold box, casting, mechanical and thermophysicalproperties.
Shan’ghin E.A.
Development of crystallization method of secondary zinc refiningfrom lead
The crystallization method of secondary zinc refining from leadimpurity based on liquation refining, used in zinc metallurgy, and monotectictransformation in the zinc-lead system is considered. A laboratory installation,which allows us to obtain cylindrical samples of 2 cm in diameter and up to 5 cm high, has been constructed using the directional top-downsolidification process. Three series of experiments have been carried out. Thespectral analysis in several points along the height of obtained samples hasbeen performed. Polluted zinc was used as material for refining; average leadconcentration was 0,26 %, 0,80 %, and 2,00 %. It is established that the toplayers of the sample are refined from zinc and the bottom layers are enrichedwith it as a result of the given process.
Key words: zinc refinement, leadimpurity, monotectic transformation.
MATERIALS SCIENCE AND HEAT TREATMENT
Gushchin A.N.
Structure and mechanical properties of prestrained welded joints of40KKhNM alloy
The results of structural state investigations and changes ofmechanical characteristics at static and cyclic loading of deformed weldedjoints made of 40KKhNM alloy are given. Quenching is shown to eliminatestructure-mechanical non-uniformity. The formation of ?-martensite owing to thedevelopment ??? transformation in the process of static deformation by tensioncan cause a considerable contribution in alloy hardening. Depending on thedegree of preliminary deformation the fatigue characteristics are variedambiguously. Technological modes are determined to provide maximum fatiguestrength at minimum rate of accumulating cyclic damages in welded joints.
Key words: mechanical characteristics,welded joints, static and cyclic loading, quenching, tension, fatigue strength,cyclic damage, technological modes.
Reznik P.L., Zamyatin V.M., Mushnikov V.S.
Thermal and X-ray micro-spectral analysis of AK6 aluminum alloy
The melting processes in AK6 industrial aluminum alloy samples inthe cast and homogenized conditions have been investigated by the thermalanalysis with the subsequent numerical differentiation in time of heatingcurves in a range of temperatures from 300 to 670 °C. Temperatures of non-equilibrium solidus, equilibrium solidus, and liquidus are established.The microstructure of cast and homogenized alloy samples is studied and thelocal chemical composition of aluminum matrix and phases is determined.
Key words: AK6 aluminum alloy, thermalanalysis, X-ray microspectral analysis, solidus, liquidus, phase.
Nosov V.K., Nesterov P.A., Shchugorev Yu.Yu.,Polyakov O.A., Grachyov N.A.
The effect of initial hydrogen concentration and vacuum annealingconditions on the structure, phase composition and mechanical properties of VT6alloy plate stocks. Part 1. The effect of initial hydrogen concentration andvacuum annealing conditions on the phase composition and mean diameter of ?-grain in VT6 alloy
The opportunities of using reversible hydrogen doping in combinationwith warm rolling for structural component refining and formation ofheterophase structure of VT6 alloy taken as an example are shown. Doping of thealloy with 0,3-0,7 wt. % hydrogen and formation of ?+?+?2-structureare accompanied by strengthening of local heterogeneity of deformation andincreasing the number of recrystallization nuclei in the course of hot sheetrolling. The dependence of initial hydrogen concentration and vacuum annealingtemperature on phase composition and the size of structural components isestablished.
Key words: phase composition, size ofstructural components, heterophase structure, VT6 titanium alloy, reversiblehydrogen doping.
CHRONICLE
- To 100-year birthday of Maria Abramovna Kolenkova
- G.A. Kolobov is 75 years old