Oil quenching of complex bodies with asymmetric elements is a
fi re hazardous, high-cost and out-of-control process. Joint bar is one of complex bodies with asymmetric confi guration. This type of heat treatment is applicable for it to meet the Technical requirements. Ecologically friendly technique and water regulated cooling device of joint bar have been developed by OJSC «VNIIMT». Due to using water as a coolant polluting emissions into the atmosphere has been completely eliminated, so there is no need of oil purchase, its replacement and disposal. Test-bench experiments at the pilot-production set resulted in obtaining the requirement level of mechanical properties in accordance with the Technical requirements. Joint bar linearity has been provided by water separate supply for each section of the pipeline. The presented
results have given occasion to acquisition of controlled cooling device process conditions. The proposed technique can replace successfully a conventional one – oil quenching.

Excess Gibbs energy change of subregular-type binary solution can be approximated with an insignifi cant error by the equation: where xi – mole fractions of components in a solution; Q0 ‒ mixing energy; m and n – numeric constants. Fixed parameters Q0 , m and n were determined by the least square method using experimental values of ΔG E and component activities of a binary solution. The obtained calculated expressions allow working with subregular solutions the same way as with regular solutions and getting simpler expressions of component activities in a multicomponent solution

Thermodynamic modeling of high-temperature interactions of microsilica and brown-coal semi-coke was carried out. Calculation of equilibrium structures of Si – O – C and Si – O – C – H systems was defi ned by a “constant” method with the use of the computer modeling program of high-temperature chemical interactions of “PLASMA”. It was established that in both systems the formation process of carbide was dominating. At stoichiometric composition of furnace charge the maximum contents in products of restoration of silicon carbide can be reached at 1700 K, and at 10 % a lack of carbon – 1900 K. The introduction of hydrogen to system doesn’t actually infl uence on the process of carbide formation that is caused by low (less than 0,001 mol) contents in a gas phase at temperatures of carbide formation of hydrocarbons and hydrocarbonic radicals. In Si – O – C system the equilibrium extent of transformation of silicon into carbide doesn’t exceed 0,97, that corresponds to the content of monoxide of silicon in a gas phase of 0,02 mol, owing to what from furnace charge of stoichiometric structure (SiO2 + 3C) it is impossible to receive the single-phase, not containing free carbon, carbide of silicon. It can be avoided using furnace charge with some (~ 10 %) lack of carbon reducer.

The article describes the calculation results of technological parameters
of metallization process of molded ore-coal materials in circular furnace with rotary bottom heated by generator gas. The circular furnace waste gases heat utilization system can be improved by means of additional contours after steam turbine, allowing to produce heat and electrical energy. The scheme of heat carrier transportation to recuperates for air and generator gas heating and to grating for spherules or briquettes heating was changed to achieve higher temperatures. The potential economic effect from the technical transformations of energy technological installation was calculated for metallization of ore-coal materials.

The article presents the solution of the problem of plastic flow
modeling in the initial stage of hot drawing of a cylindrical workpiece in a forging press with combined strikers. The intensity stress fi eld for the tensor of total elastic stresses (load and thermal ones) has been received. The stress load has solved the problem of plane deformation for a workpiece of a circular cross section to which three lumped linear efforts were attached. The zone of a plastic fl ow was determined by the value of the yield strength of the material as a limitation of the elastic stress intensity. It has been shown that the tensile thermal stresses involve a near-surface layer of the workpiece into a zone of a plastic fl ow; that facilitates the process of forging. The numerical example of the formation of stress loads and thermal stresses during drawing after roughing-up of 7-ton ingot of 40KhN steel with the radius of average cross-section R = 0.35 m; its bottom (880 °C) boundary of the admissible
forging temperatures was reached in 20 minutes after removal from the furnace with a temperature of 1180 °С has been considered. The graphs of the component distribution of the tensor of stress loads and thermal stresses have been introduced, as well as the respective intensities of stresses in the cross-section of the workpiece.

The paper considers technological options of converter melting
when using two-level lances of different design. The formation peculiarities of metal and slag scaffold on the surface of two-level oxygen lances at top bath blowing of 160-ton converters, depending on the blowing progress with different levels of foamed slag-metal emulsion formation in the working space of the aggregate are reported. An adjoined three-dimensional mathematical model of hydrodynamic and mass-transferring processes in the slag and metal converter phases is proposed; it can be used for the study of circulation process regularities in the converter cavity at different positions of two-level lance, nozzle number in the upper and lower levels, nozzle angles of inclination, the oxygen consumption through the nozzle and other process parameters. Numerical simulation of metal blowing in a 160-ton converter with the use of two-level lance with fi ve Laval nozzles in the bottom tip and eight nozzles in the top row was carried out. These data form an idea of the nature of the metal and gas and slag phase in the converter.

Experimental study of the effect of the introduction of carbonfl
uorine additives containing 14,01 – 22,72 % Al; 13 – 22,04 % F;
13,16 – 21,34 % C; 8,27 – 13,4 % Na; 0,09 – 0,14 % K; 0,66 – 1,09 % Ca; 26,11 – 42,35 % SiO2 ; 1,15 – 1,86 % FeO; 0,07 – 0,12 % MnO; 0,001 – 0,1 % MgO; 1,47 – 2,38 % S; 0,03 – 0,05 % P into oxidative fl uxes AN-348, AN-60, AN-67 when welding of steel 09G2S and aluminate-base OK Flux 10.71 fl ux at welding of steel 10HSND has been carried out. In the experiments it has been shown that from the point of view of the exclusion of formation in the weld of non-metallic inclusions, it is optimal to use carbon as a deoxidizer, as formed with the participation of gaseous carbon compounds (CO and CO2 ) are easily removed and do not contaminate the weld metal with non-metallic inclusions. The studies have shown that the carbon-fl uorine-containing additive in the composition of the fl uxes has a positive effect on the quality of the weld. It has been found out that when using the analyzed additives in the amount of 4 - 6% in the data fl uxes the overall oxygen content in the weld reduces. Fractional gas analysis revealed that the largest number of aluminates and silicates adversely affect the physico- chemical properties of welded joints, contained in the submergedarc welding of AN-60 and OK Flux 10.71, with the introduction of additives the reduction of these compounds has been observed, while in AN-348 and AN-67 fl uxes changes have been insignifi cant. When using the proposed additives the required mechanical properties, as well as impact strength at low temperatures by reducing contamination of the weld with oxide non-metallic inclusions increase, and the concentration of carbon in the weld remains at the level of the base metal.

The regularities of structure-phase states and defect substructure
transformations of the rail surface layer with the 10 mm depth under continuous service (the passed tonnage of 1000 million ton of gross weight) have been revealed by the methods of modern physical material science. The microhardness profi les have been constructed and the reduction of the strength characteristics of the rolling surface after the rail operation on the railr ad has been revealed. Operation of the rails leads to the formation of the multilayer structure. It has been shown that the surface layer with the ~20 μm depth has a multiphase submicro- and nanocrystal structure and contains micropores and microcracks. The layer structure located at a distance of 2 mm from the rolling surface is morphologically similar to that of the steel before the operation and it is presented predominantly by perlite grains of lamellar morphology, grains of ferrite-carbide mixture and structurally
free ferrite grains. The increased density of bend extinction contours at the depth of 2 mm from the rolling surface have been noted and it has been shown that maximum amplitude of stress fi elds is formed at the interphase globular particle-matrix density.

Changes in the microstructure of the surface layer of NiTi after
pulse impacts on the alloy surface by medium energy silicon ion beams were investigated by the electron backscattered diffraction method. It was found that the surface layer was characterized by the presence of the martensitic phase В19′ within the fragmentation grain structure with the high concentration of phase and interphase boundaries, the linear fragment sizes exceeding 1 micron; grain fragmentation was inhomogeneous and depends on the crystallographic orientation of the initial grain. Internal structure of the one grain was fragmented by almost 1/3 of its volume, and in the other grain any signifi cant structural changes was not observed. The most heavily fragmented structure was observed in grains, which crystallographic orientation was close to the direction <111>, relative to the impact direction. The angles misorientation of the fragments was analyzed relative to the original crystallographic orientation B2 structure.

The authors proposed the complex technology of surface hardening
of titanium alloys based on a combination of surface alloying with
boron and carbon, electromechanical treatment (EMT) and non-abrasive ultrasonic fi nishing (NUF). The results of the study of microhardness and features of the structural-phase state of the surface layer of 5V titanium pseudo-α-type alloy were presented after various combinations of treatments (EMT, NUF, surface alloying). It was shown that for a variety of schemes hardening was achieved by increasing the surface microhardness of the treated material to 30 – 40 %. The greatest effect can be observed when using alloying agent during EMT + NUF (graphite cast powder in combination with an organic binder). Increase in microhardness was provided due to the hardening by severe plastic deformation of the metal, grain size refi nement (from 50 to 1 μm) during phase transitions, as well as the formation of fi ne reinforcing  borides and carbides of titanium (whose content in the surface layer increased up to 1.88 and 0.46 %, respectively).

The problem of modelling of a discrete-continuous dynamic process with lack of current control values is discussed with the formulation of identifi cation problem. A nonparametric model of dynamic object and nonparametric identifi cation calculation results are given due to incomplete information about control actions. A dual scheme of dynamic object control system is submitted in order to include uncontrolled inputs. The internal control frame includes the unit with a typical control mode. The upper control frame involves a nonparametric regulator which has self-training and dual sense properties. A nonparametric algorithm of dual control is described and its dual nature is analyzed. Comparative calculation results of the dynamic object control system with dual scheme and with PI-controller are submitted.

The paper presents formulas to simplify the analytical calculation of axial-symmetric plastic deformation processes along the streamlines and describes geometric singularity of the optimization solution results of the problem on extrusion of a cylindrical workpiece in a conical matrix.

The multilayer preform production is possible with the use of
electroslag technology that is highly variable and allows to varify the
infl uence ways to the structure of the resulting casting. According to
the proposed technology the forming of layers with new composition
was made by supply of carbonaceous material with specifi c weight into the liquid-metal bath at specifi ed intervals. In order to determine the changes caused by the introduction of additives, a series of mechanical tests were conducted, in particular – the defi nition of microhardness of the resulting material. Metallographic studies of microhardness with yield results that are not possible in macroscopic mechanical tests. For example, it can be used to identify the pattern of change of hardness values in a multi-metal composition. Analysis of the data allows to conclude: microhardness of the material, with a lot of additives is higher than with a smaller mass-carburizers additives; on transverse specimens – microhardness is higher than longitudinal; samples were subjected to a deeper degree of deformation and heat treatment and annealing conditions for annealing hardening + microhardness results show values almost two times higher. Also worth mentioning - profound
degree of deformation leads to a smearing of the material layers
in the structure, and defi nes the maximum degree of deformation of the material in which the multilayer structure is preserved.