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The results of studies of the process of obtaining wire for the manufacture of jewelry chains from new nickel-free 585 gold fineness alloys are presented.New 585 gold fineness alloys, alloyed with palladium, silver and other elements, and as modifiers - with rhodium and ruthenium in the stated quantities have been proposed.By modeling the process of section rolling of rods in octagonal calibers using the variation method of minimum total power, the broadening of the metal and the energy-power parameters of rolling rods from the investigated alloys have been determined. The regularities of their change have been found. Software has been developed for designing processes for the production of longish deformed semi-finished products and technological modes of rolling and drawing of new gold alloys.With the help of experimental studies, the adequacy of the results of calculations and modeling was checked and new data were obtained on the mechanical properties of the metal and its structure.It has been found that the proposed alloys and the modes of their processing using the processes of section rolling and drawing make it possible in industrial conditions to obtain jewelry wire with a diameter of up to 0.25 mm with the level of mechanical and operational properties required for chain tying.

The results of experimental studies on the development of a method for obtaining titanium-containing bar ligature, the study of its structure and modifying ability are presented. The distinctive features of the new technology are the use of titanium sponge and/or titanium shavings as titanium raw materials, the primary alloying of aluminum with titanium, and then boron, the introduction of titanium in two stages: initially, 2/3 of the titanium metal raw materials are dissolved in the aluminum melt, and the remaining amount is introduced after the reduction of potassium tetrafluoroborate. Pre-impregnation of the titanium sponge with halide-containing flux and the use of a briquetted mixture of KBF4 + Al-powder are also provided. The experimental technology for the preparation of the Al–Ti–B melt is described, the extraction of titanium and boron into the ligature is calculated, its microstructure is investigated, and the chemical and molecular compositions of the resulting slags are determined. Deformation treatment for the production of bar ligature was carried out by the method of direct extrolling which made it possible to level the defects of the cast structure. It is established that the use of high-speed crystallization-deformation in the implementation of the combined direct extrolling process makes it possible to obtain alloying bars of a given diameter at minimal energy consumption with the required complex of mechanical and operational properties. A quantitative assessment of the modifying ability of the experimental cast-iron ligature and the deformed cast-iron rod obtained by the direct extrolling method was carried out in comparison with the mass-produced cast-iron ligature produced by KBM Affilips (the Netherlands/Belgium). Based on theoretical and experimental studies, the composition and technology for producing Al–Ti–B modifying ligature using titanium sponge and/or shavings and potassium tetrafluoroborate with a content of 3.0 ± 0.3% titanium and 1.0 ± 0.2% boron as alloying additives have been developed, which meets the requirements for the composition of aluminum ligatures.

The results of studies on the production of welding wires with a diameter of 2.5 and 3.3 mm from alloy 1580 are presented. To compare the manufacturability of the processing, various methods were used to obtain billets for drawing with a diameter of 8-12 mm: the traditional method of direct hot extruding (discrete); combined rolling-extruding method; and ingotless rolling-extruding method (continuous). The developed modes of bar rolling, drawing and annealing made it possible to obtain prototypes of wire in laboratory and industrial conditions. It was found that alloy 1580 is highly manufacturable both with the traditional method of pressure treatment (extruding) and with combined rolling-extruding methods. It was revealed that the application of all methods makes it possible to obtain billets with the level of mechanical properties necessary for further multi-operation processing. Based on the results of research obtained in laboratory conditions, rational drawing modes for industrial wire production have been developed. As a result of bay drawing, pilot batches of welding wire with a diameter of 3.26 and 2.47 mm from alloy 1580 were obtained, which was successfully used for welding sheet metal.

This article present the results of studies of the process of wire drawing from the PdNi-5 alloy, performed using computer simulation in the DEFORM 3D software package. В качестве материала для исследований использовали сплав с содержанием 95% палладия и 5% никеля. An alloy with a content of 95% palladium and 5% nickel was a material for research. The patterns of changes in the stress-strain state for the current processing mode determined, and a more rational drawing mode with a redistribution of drawing coefficients along transitions proposed. For the proposed regime, using the created model, the values of drawing stresses, drawing forces and Cockcroft-Latham criterion determined. It was found that the stress distribution in the deformation zone corresponds to the generally accepted laws of their change, and their maximum values are realized in the metal located in the calibrating zone of the drawing die. In addition was revealed that the stresses in the current mode have limit values at the second and fourth passes. The redistribution of deformation indicators in the proposed mode allowed reduce the magnitude of these stresses and, thereby, reduce the likelihood of wire breaks. The maximum value of the Cockcroft-Latham criterion is achieved in the last transitions, but at the same time, destruction will not occur, since they do not exceed the limit value. The drawing force also decreases with the implementation of the proposed mode and does not exceed the permissible values regulated by the technical characteristics of the equipment. Since it is the proposed mode of wire drawing, it is characterized by a decrease in energy power indicators and the likelihood of wire breakage in the process of metal deformation it can be recommend it for implementation in existing production.

The results of studies of the structure and properties of semi-finished products from aluminum and its alloys, obtained with the use of cast-free rolling-extruding are presented. It has been found that the rods obtained by the high-speed crystallization-deformation technology by the direct rolling-extrusion method have a stable ultrafine subgrain structure, which makes it possible to use them as modifiers. Experimental studies have been carried out, which confirmed the assumption that the initial structure of the modifying rod affects the melt. It was revealed that the size and density of distribution of additional crystallization centers formed in the volume of the melt based on clusters are inherited from the original subgrain structure of the modifying rod made of aluminum or its alloys. Metallographic studies have also shown that the subsequent severe plastic deformation by equal-channel angular extruding of rods obtained by direct rolling-extruding from an experimental alloy of the composition Al-0.2Zr-0.2Fe-0.4Mg makes it possible to achieve additional strengthening of the metal, since even more refines its structure, while the average grain size is 647 μm.

This article represents the results of studies of the drawing thin wire from the alloy Pd-5Ni process. The studies used the software developed by the authors using the methods of calculating the drawing process and the computer model implemented in the DEFORM 3D software package. By way of calculation, a drawing route was determined, including 14 transitions, and the efforts of deforming the metal were found when producing wire with a diameter of 0.075. For this mode of deformation processing using the DEFORM 3D software package, we simulated the drawing process and established the temperature and stress distribution over the volume of the workpiece. The simulation results confirmed that the calculated safety factor for drawing is in the range of 2.85-3.43, which ensures a stable process of deformation of the metal without breaks and, as a consequence, an increase in productivity and yield of the suitable metal. Experimental studies have confirmed the adequacy of the developed model, so it can be used to analyze the process of drawing wire from other precious metal alloys. The results of the research are recommended to improve the production technology of thin wire from the alloy Pd-5Ni for the manufacture of catalytic gripping grids.

This article presents the results of the study of the joint effect of the processing conditions of the new composition of the Al-Zr system alloy by combined casting and rolling-extruding and two-stage annealing on the structure and properties of round bars used in the manufacture of heat-resistant wires. The research show patterns of changes in the properties, the specific electrical resistance of the bars, depending on different conditions of deformation and heat treatment of aluminum alloy with a content of 0.3% zirconium and 0.2% iron. The results of micro-X-ray spectral analysis and the granular structure of the samples before and after two-stage annealing confirming the stability of the structure after heating and preserving the strength of semi-finished products. Presented parameters of combined casting and rolling-extruding and two-stage annealing for the manufacture of rods from the studied alloy make it possible obtaining good combination of mechanical properties and electrical conductivity.

The paper presents the study on mechanical and corrosion properties of rolled sheet products from a new alloy of the Al-Mg-Sc system in a deformed and heat treated state. Its use and development of technologies for the production of relevant parts for automobile and shipbuilding industries are important today due to the tasks of downstream aluminum processing, which are solved by RUSAL, and confirmed by the state support of a comprehensive project aimed at creating a high-technology production division, being currently carried out by the Bratsk Aluminium Smelter and Siberian Federal University. To determine mechanical and corrosion properties, the authors used sheets and coils rolled on industrial reversing hot rolling mill Quarto 2800. The tensile test was used to study deformed samples after rolling and samples produced in five heat treatment modes with varying heating temperatures of 300, 350 and 380°C and a soaking time of 1 and 3 hours. The studies on samples of rolled products with various thicknesses showed that as compared to the initial state, steel strength properties after heat treatment decrease by 12–20% on average, and ductility properties (δ) increase by 50–65%. In this case, heat treatment modes 1–3 give a fairly good ratio of strength and ductility properties. The level of these properties is comparable to the properties of alloy 01570. It is noted that a trend in a decrease in strength properties and a growth of ductile properties with increasing heat treatment temperature is also observed for samples of rolled products produced by various methods of cold rolling (cut-to-length sheets and in coils). If sheet thickness is similar, strength properties are higher, when sheets are cut-to-length rather than in coils. The corrosion tests of sheets with different thicknesses showed that the heat treatment modes under study do not have a significant influence on alloy resistance to intergranular corrosion.

Results of researches of process of hot rolling of ingots from the experimental aluminum alloy which is economically alloyed by scandium are given. The computer model of process of hot rolling with the use of which the straining, temperature and speed processing modes conditions is calculated and also power parameters of processing is calculated in applied to industrial conditions. It is shown that the use in the model of a certain shape of the ingot faces (Petrov's lock) and indirect rolling action in the edging stand is made it possible to reduce the likelihood of the formation and further development of micro cracks on the edges of rolled metal. The adequacy of results of modeling was confirmed by carrying out pilot-industrial tests when rolling large-size ingots from the experimental alloy and obtaining batches of hot-rolled plates and sheets of various sizes. The tensile test was used to study deformed samples after rolling and samples obtained on five regimes of heat treatment with varying heating temperatures of 300, 350 and 380 oС and holding time in the furnace for 1 and 3 hours. The results of the studies on samples of hot-rolled sheets 10 mm thick showed that, compared with the initial state, the strength characteristics of the metal after heat treatment are reduced by an average of 12-20%, and plastic characteristics increase by 50-65%. In this case, the heat treatment regimes 1 - 3 give a good ratio of the ductility and plastic properties of the metal.

The paper presents the results of studies of the structure and properties of a wire with a diameter of 0.5 mm from an alloy of the Al-REM system with a rare-earth metal content of 7-9%. Wire obtained as a result of the implementation of the technology of its manufacture using the methods of casting into an electromagnetic mold (EMM), continuous extruding and drawing.The rheological properties of the metal of continuously cast round billets from the experimental alloy obtained using an electromagnetic mold are determined. The modeling and analytical assessment of the possibility of carrying out the process of combined rolling-extruding (CRE) of such billets in a closed box-type roll groove of a continuous extruding unit are carried out. The features of metal shaping have been studied. The temperature-speed and technological parameters was found at which the CRE process can be carried out in a stable mode of operation. Data have been obtained for the forces acting on the die and rolls and the moments on the rolls during rolling-extruding.The results of experimental studies of the process of obtaining longish deformed semi-finished products from an experimental alloy on the laboratory unit CRE-200 and the pilot plant unit CRE-400 are presented. The structure of the metal has been studied; data on the ultimate tensile strength, yield strength, relative elongation, and electrical resistivity of hot-extruded rods and wires in cold-worked and annealed states have been obtained.It was found that the proposed processing modes make it possible to obtain by the method of combined rolling-extruding rods with a diameter of 9 mm in industrial conditions from longish billets with a diameter of 18 mm, cast by means of EMM. Wire in a cold-worked and annealed state with a diameter of 0.5 obtained by drawing from the rods with a diameter of 9 mm from an experimental alloy of the Al-REM system containing 7-9 rare earth metals with the required physical and mechanical properties.

The results of studies of the combined processing of alloys of the Al-Mg-Sc system with known rheological properties under various temperature-rate and deformation conditions are presented. A computer model of the combined machining process was created and the DEFORM 3D complex was used to analyze the metal flow, the distribution of the strain rate and the temperature of the metal over the cross section of the workpiece when receiving round bars of various diameters. The results of the research were used to develop the production technology of welding wire from alloys of the Al-Mg-Sc system.

Development of electrical alloys of system aluminium - rare-earth metals and aluminium-zirconium for production of electrotechnical application wire rod. Design of technological line for their manufacturing.