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The article presents the results on the structure formation of deposited coatings obtained from steel chips P6M5 subjected to diffusion nitrogen-carbon doping. It was found that the diffusion doping with nitrogen-carbon steel chip waste P6M5 carbon content in them varies between 1.75–3.14%, nitrogen – 0.43–1.24%. The phase composition includes phases: a-Fe, M6C, Fe3C, (Cr, Fe)2N1–x, Fe3N, Cr0.63C0.35N0.03, M4(C, N) depending on the temperature and time of diffusion doping. When surfacing these materials in the deposited coating contains carbide-forming elements 8,6–9,3%, carbon 1,04–1,94%, nitrogen 0,08–0,25%. The structure consists of carbide M23S6, martensite and austenite, while the content of austenite in dendrites can reach 70–90%. It is shown that nitrogen doping of the deposited coatings obtained from steel chips P6M5, subjected to saturation with nitrogen-carbon, more effectively increases the amount of austenite in the structure than alloying the deposited coatings with nitrogen ferroalloys.

Various modifiers are used for non-furnace processing of cast iron. Some of them are designed for inoculating modification, which improves mechanical properties and eliminates the appearance of whiteness in castings, while others are designed for spheroidizing processing, in particular for producing cast iron with spherical and vermicular graphite. Some have both spheroidizing and inoculating properties. The main part of inoculating and spheroidizing modifiers is made on iron-silicon, Nickel and copper bases.In addition to the chemical composition, the size of the modifier particles, as well as their shape, are of great importance for modification. The optimal size of the fraction depends significantly on the non-furnace processing technology. Thus, for the larger the bucket and the longer the casting the longer the modification effect is required. One of the methods to achieve this is to increase the particle size of the modifier to 50 mm. When intraform processing of cast iron with spherical and vermicular graphite, magnesium-containing modifiers have strict limits on the upper size (4...5 mm), and in addition, the content of small fractions (less than 0.6...1 mm) is not allowed.The use of «heavy» magnesium-containing ligatures for spheroidizing modification of cast iron in order to obtain higher physical and mechanical properties has scientific and practical interest. Numerous studies show that for maximum effect the formation of the structure of the spheroidal graphite, dispersed pearlite metallic base of SGI (spheroidal graphite iron) relevant question is not only selection of the chemical composition of magnesium alloys, but also of the fractional composition, as well as effective method of input into the liquid melt.The purpose of this work was to study the technological features of obtaining cast iron with spherical graphite by bucket modification of copper-magnesium ligature.The researchers used a Leo–1420 scanning microscope, a Polam l-213 optical microscope, and a VEGA II LMU electron microscope with an INCA ENERGY 350 microanalyzer. High-speed induction melting plant, a set of equipment for analyzing the technological and mechanical properties of high-strength cast iron were used.Earlier experimental studies have shown the real possibility of obtaining in the laboratory a «heavy» copper-magnesium alloys as the alloying of magnesium metal with copper, followed by rapid cooling with use of rolling and plastic deformation of powder alloys. Analysis of test results of samples of such alloys showed that it depends on the value of its additives into liquid iron in the structure of formed graphite phase in compacted and globular form. At the same time, the metal base of cast iron is additionally alloyed with copper, which has a favorable effect on the strength characteristics of SGI.However, an urgent problem is the possibility of the appearance of a cementite phase in the structure of high-strength cast iron as a result of its increased supercooling due to the process of spheroidization of the graphite phase. This phenomenon is compounded by the fact that the copper-magnesium ligature, in contrast to the «light» ligature, does not contain silicon active graphitizer. This feature must be taken into account when obtaining high-strength cast iron of high grades.

Researches on distribution of chrome and copper in the fused coating received from the superficial alloyed wire by boron with in additionally applied electroplated coating of chrome and copper were executed. The structure of the fused coating consists of dendrites on which borders the boride eutectic is located. It is established that the content of chrome in dendrites is 1,5– 1,6 times less than in the borid; distribution of copper on structure is uniformed. Coefficients of digestion of chrome and copper at an argon-arc welding from a wire electrode with electroplated coating are established. The assimilation coefficient for chrome is equal to 0,9–1,0; for copper – 0,6–0,75.

The increase of efficiency of modification process for ductile iron is topically, thereby increasing its mechanical and operational properties. For these purposes, in practice, various magnesium containing alloys are used, including «heavy» ones on the basis of Copper and Nickel. The analysis has shown that the application of bulk inoculating alloys based on copper basis were not effectively due to long dissolution period. From this point of view, the interest is high-speed casting, allowing the production of inoculating alloys in the form of strips – chips that are characterized by a low dissolution time and low piroeffekt. The aim of this work is to study the features of structure formation in nodular cast iron using different spheroidizing alloys based on copper. Studies have shown that the transition from the use of briquetted form alloys based on copper and magnesium to the «chips-inoculating alloys» allowed increasing the efficiency of the spheroidizing process. Further improvement in the quality of ductile iron can be achieved by the use in «chip-inoculating alloys» additives of nanosized yttrium oxide powder.

The research carried out in laboratory of metal science on detection of hydrogen presence in reinforcement depending on period of aging and reinforcement profile and also its influence on plastic properties of reinforcing bar is described in this article. The method of glycerine tests was applied for identification of hydrogen presence in finished reinforcing bar, the essence of which is in the fact that at gas emission from metal the bubbles stay too long on the surface of cross samples under glycerin layer. The revealed regularities enable to recommend actions for providing stable mechanical properties of the heat-strengthened reinforcement by creation of conditions for lowering of steel saturation with hydrogen, preventing thereby occurrence of hydrogen embrittlement of reinforcement on JSC «BMZ» – management company of holding «BMK».

The regularities of carbon diffusive impregnation with carbon, nitrogen and boron of micro-objects of tool steels waste are established

The nonmetallics in the samples of 10 meltings of steel of grade 80 and 42Cr4Mo2 before and after vacuumization are investigated.

The working of patenting-brassing unit No 6 StPTs-2 is examined. It is shown that optimization of temperaturetime mode of furnace of patenting allowed to increase the parameter of unit from DV76 till DV96.

Influence of thermal processing on structure and characteristics o f economically-alloyed high-duty cast iron is shown.

The results of investigations of mechanical characteristics and structures of steels for the technological accessory, recovered by means of electroslag technologies, which are economically efficient ways of stamps recovery are presented. The contents of nonmetallic impurities in metal after electroslag heating is considerably reduced, the impurities are becoming more dispersed and are distributed in ingot volume more uniformly. The characteristics of plasticity and viscosity after electroslag heating are practically equivalent to these characteristics for deformed metal and cost of the stamp recovered by means of electroslag heating is considerably lower than the cost of accessory of deformed metal.