The results of a study on the strength of rolled products from aluminium alloys doped with scandium under various processing conditions of hot and cold rolling are presented. The regularities of metal flow and the level of strength of deformed semi-finished products from aluminum-scandium alloys are established, depending on the total degree of deformation and the various modes of single reduction during rolling. It is shown that when using one heating of a cast billet to obtain high-quality semi-finished products, the temperature during the rolling process should not be lower than 350-370°, and the total degree of deformation does not exceed 50-60%. It was found that the semi-finished products from alloys with a content of scandium in the range 0.11-0.12% in the deformed state had elevated values of ultimate tensile strength and yield strength of the metal, which allows them to be recommended for industrial production of sheet metal products.

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.

2«RUSAL Bratsk Aluminum Smelter» JSC, 665710, Bratsk, BrAS, 1, Russia a sbs270359@yandex.ru Keywords: aluminum alloys of the Al-Mg system, scandium, rolling, extruding, sheet semi-finished products, welding wire, mechanical properties, corrosion resistance.Abstract. The combination of weldability, corrosion resistance and sufficient strength make it possible to use deformed semi-finished products from the Al-Mg system alloys for sheathing ships' hulls, in car, aircraft and rocket construction, as well as in other areas of industry. To increase the strength characteristics, it is promising to alloy them with small additives of metals such as titanium, zirconium, scandium, and others. In this paper, studies were carried out to obtain deformed semi-finished products (strips, rods and wires) from aluminum alloys in which the scandium content varied from 0.1 to 0.25%. For this purpose, various metal treatment conditions simulated in the laboratory of School of Non-Ferrous Metals and Material Science in Siberian federal university. For the preparation of sheet semi-finished products regimes of hot and cold rolling of a cast billet simulated from a thickness of 40 mm to a thickness of 3 mm. For the preparation of sheet semi-finished products, the modes of hot and cold rolling of the cast billet from a thickness of 40 mm to a thickness of 1-3 mm have been modeled. To produce a welding wire with a size of 2×2 mm, a combined casting and rolling-extruding (CCRE) process was simulated to produce a 9 mm billet and its further rolling in square gauges. Rods with a diameter of 9 mm were produced on a combined processing unit, and wire on a rolling mill with a roll diameter of 130 mm. In accordance with the research program, the mechanical properties of hot-deformed, colddeformed and annealed sheet semi-finished products were measured. Then the semi-finished products were welded together with the obtained wire and the quality and properties of the welded joint and their corrosion resistance were evaluated. Research results are currently used to develop industrial technologies for the production of sheets and plates from experimental alloys of the AlMg system doped with scandium.

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.

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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.

Сибирский федеральный университет, г. Красноярск ОАО «РУСАЛ Братский алюминиевый завод» Статья поступила в редакцию 14.05.19 г., доработана 19.07.19 г., подписана в печать 26.09.19 г. Введение В настоящее время более 50 % всего мирового использования металла приходится на строительство и транспорт, причем деформированные полуфабрикаты из алюминиевых сплавов широко востребованы в судо-и автомобилестроении. Применение передовых технологий в этом сегменте промышленности является стратегически важной задачей, так как к автомобильной и судовой технике предъявляются высокие требования по 1 Сидельников С.Б. -докт. техн. наук, проф., зав. кафедрой обработки металлов давлением (ОМД) Института цветных металлов и материаловедения (ИЦМиМ) Сибирского федерального университета (СФУ) (660025, г. Красноярск, пр-т им. газеты «Красноярский рабочий», 95).