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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 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 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 boxtype 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.

ВведениеВ настоящее время одной из актуальных задач при изготовлении продукции электротехнического назначения является разработка новых технологий совмещенной обработки для получения длинно-мерных полуфабрикатов в виде прутков, проволоки или катанки из алюминиевых сплавов, содержащих редкоземельные металлы. Приведены данные экспериментальных исследований по определению механических свойств длинномерных деформи-руемых полуфабрикатов в виде прутков и проволоки из сплавов алюминия с редкоземельными металлами, полученных с использованием методов совмещенной обработки. Применение совмещенной технологии литья, прокатки и прессования дает возможность увеличить прочность горячепрессованных прутков в среднем на 15-20 % по сравнению с совмещенны-ми процессами прокатки и прессования литой заготовки, полученной в электромагнитном кристаллизаторе. Показано также, что уменьшение содержания РЗМ в сплаве приводит к снижению прочностных и повышению пластических ха-рактеристик. При этом, варьируя величиной суммарной степени деформации при волочении и применяя отжиги, можно управлять уровнем физико-механических характеристик конечной продукции.Ключевые слова: алюминиевые сплавы, редкоземельные металлы, литье, прокатка, прессование, совмещенные методы, механические свойства, пластичность, прочность.The data of experimental studies on determining the mechanical properties of long-length deformed semifinished products in a form of bars and wire made of alloys of aluminum with rare-earth metals, which are fabricated using the combined treatment methods, are presented. The application of the combined technology of casting, rolling, and pressing makes it possible to increase the strength of hot-extruded rod by 15-20 % on average compared with combined rolling-extruding the cast billet formed in an electromagnetic crystallizer. It is also shown that a decrease in the REM content in the alloy leads to the strength reduction and an increase in plastic characteristics. Herewith, it is possible to control the level of physicomechanical characteristics of the final product varying the summary deformation ratio during drawing and applying annealing.

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.