Vol 2016, No 12 (2016)

A procedure for the calculation of gas release from arc furnaces is presented. The procedure is based on the stoichiometric ratios of the oxidation of carbon in liquid iron during the oxidation heat period and the oxidation of iron from a steel charge by oxygen in the period of solid charge melting during the gas exchange of the furnace cavity with the external atmosphere.

The problems of increasing the efficiency of electrosmelting of steel using a system of supplying prereduced pellets through tube (hollow) electrodes are considered. The application of the energy-saving conditions based on the new developed technology is shown to intensify the processes of slag formation and metal heating and decarburization. It is experimentally found that the local supply of iron-ore prereduced pellets under electric arcs into a foamed slag favors a substantial decrease in the dust loss and the metal loss upon melting.

The effect of a secondary metallurgy technology on the metal quality during the production of lowcarbon corrosion-resistant steels is estimated. The content of a modifier introduced is found to principally influence the types of inclusions and, via them, the corrosion resistance of parts from the metal subjected to deep refining from sulfur and nonmetallic inclusions.

The methodology and the experimental studies of the influence of an atmosphere on the wetting of titanium carbide with liquid low-carbon steel in various atmospheres are presented. The wetting of titanium carbide in an oxidizing atmosphere is found to be limited (the wetting angle is 97°–110°), while complete wetting takes place in vacuum and in an argon atmosphere.

The effect of the rotation of an arc on the weld formation in welding 1565chM alloy sheets is studied. The arc rotation is shown to induce controlled low-frequency perturbations, which depend on the tungsten electrode rotation frequency, in a weldpool. Periodic changes in the value and direction of temperature gradient favor misorientation and refining of the weld structure. The arc rotation in welding intensifies the release of gas bubbles and oxide inclusions from a weld.

The parameters of plasma–arc reduction melting of a charge of the carbon-containing leucoxene concentrate from the Yareg deposit are calculated, and the experimental data obtained on the basis of the calculated parameters are presented. Synthetic rutile with 3–4% silicon was synthesized.

The results of studying the efficiency of application of protective coatings on GTE turbine blades are presented. The efficiency of application of protective coatings in the production and repair of the blades is considered.

The processes occurring in arc discharges are analyzed as the sources of acoustic radiation in an electric arc furnace (EAF). Acoustic vibrations are shown to transform into mechanical vibrations in the furnace laboratory. The shielding of the acoustic energy fluxes onto water-cooled wall panels by a charge is experimentally studied. It is shown that the rate of charge melting and the depth of submergence of arc discharges in the slag and metal melt can be monitored by measuring the vibrational characteristics of furnaces and using them in a universal industrial process-control system, which was developed for EAFs.

The results of thermodynamic analysis of the vacuum–melt–ceramic system and experimental investigations of using up to 100% wastes during vacuum-induction melting are presented. An important role of rare-earth and alkaline-earth metals and heat treatment is shown for effective refining of a melt from impurities and gases. As a result, a resource-saving technology of making advanced cast and deformable nickel superalloys is developed with allowance for processing all types of wastes, including off-grade wastes. The developed technology of refining wastes under vacuum makes it possible to manufacture the alloys that fully meet the requirements of alloy specifications from 100% wastes. This technology is now used for the mass production of nickel superalloys in a research complex at FGUP VIAM.

The open trade on the world market is estimated using information of one-day exchange prices of nonferrous and precious metals, oil, reduced crude, and gasoline and the main world stock indices in the time period from January 1, 2009 to December 31, 2015. It is found that the short-term changes in the prices of nonferrous metals are determined by the prices on the metal market. The changes in the prices of energy carriers and the stock trade on the stock market weakly influence the pricing of nonferrous and precious metals. The prices of metals depend on the situation during trade on commodity exchanges, and the stock market indirectly influences the exchange prices of metals through changes in the share prices of the companies that produce copper, aluminum, and zinc.